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Diamond-like Carbon (DLC) has been used as a coating material of choice for a variety of technological applications owing to its favorable bio-tribo-thermo-mechanical characteristics. Here, the possibility of bringing DLC into orthopedic joint implants is examined. With ever increasing number of patients suffering from osteoarthritis as well as with the ingress of the osteoarthritic joints malaise into younger and more active demographics, there is a pressing need to augment the performance and integrity of conventional total joint replacements (TJRs). Contemporary joint replacement devices use metal-on-polymer articulations to restore function to worn, damaged or diseased cartilage. The wear of polymeric components has been addressed using crosslinking and antioxidants; however, in the context of the metallic components, complications pertaining to corrosion and metal ion release inside the body still persist. Through this review article, we explore the use of DLC coatings on metallic bearing surfaces and elucidate why this technology might be a viable solution for ongoing electrochemical challenges in orthopedics. The different characteristics of DLC coatings and their feasibility in TJRs are examined through assessment of tribo-material characterization methods. A holistic characterization of the coating-substrate interface and the wear performance of such systems are discussed. As with all biomaterials used in TJRs, we need mindful consideration of potential in-vivo challenges. We present a few caveats for DLC coatings including delamination, hydrophobicity, and other conflicting as well as outdating findings in the literature. We recommend prudently exploring DLC films as potential coatings on metallic TJR components to solve the problems pertaining to wear, metal ion release, and corrosion. Ultimately, we advise bringing DLC into clinical use only after addressing all challenges and concerns outlined in this article.

High hardness, low friction coefficient and chemical resistance are only a few of the exceptional mechanical qualities of diamond. Diamonds can be artificially created to have different levels of conductivity, or they can be single, micro or nanocrystalline and highly electrically insulating. It also has high biocompatibility and is famous for being mechanically robust. Due to its high hardness, lack of ductility and difficulty in welding, diamond is a challenging material to construct devices with. Diamonds have experienced a rise in attention as a biological material in recent decades due to new synthesis and fabrication techniques that have eliminated some of these disadvantages. In general, entropic measurements are used for investigating the chemical or biological properties of molecular structures. This study calculates several important K-Banhatti entropies, redefined Zagreb entropies and atom-bond sum connectivity entropy for diamond crystals. We also present a numeric and graphical explanations of obtain indices., Validerad;2024;Nivå 2;2024-09-09 (hanlid);Funder: KingSaud University, Riyadh, Saudi Arabia (RSP2024R401);Full text licens: CC BY-NC

Magnetic imaging is a critically important capability in the study of biological systems. Iron oxide minerals exist within ferritin proteins, the iron carriers found in blood; they provide structural integrity to the teeth of limpets and chiton; and the magnetism of magnetite enables magnetotactic bacteria to sense the magnetic field of the earth. However, many interesting magnetic iron oxides impose challenging magnetic imaging requirements. The size of biomagnetic minerals are often small, along the respective magnetic moments of the minerals. Additionally, the structural and chemical properties of biological material involved in imaging experiments often place additional demands on the imaging environment. Quantum magnetic imaging is a technique which is finding a wide range of biological applications. The combination of the spatial resolution, imaging throughput, magnetic sensitivity and versatility of operation provide the technique an important niche among magnetic imaging techniques, and enables the study of samples which would be impractical to study using other magnetic imaging methods. One such example where quantum magnetic imaging can overcome experimental challenges is the study of magnetoreception. Magnetoreception has been well established through behavioural studies as being of use for navigational purposes to a large range of widely varying species. Quantum magnetic imaging provides a means to analyse the magnetic properties of potential magnetic particle based biocompasses. Magnetic images can be correlated to optical brightfield images, which reduces the likelihood of false positives being reported. The magnetic susceptibility of magnetic particles found can be measured by examining the relationship between the applied field strength and the stray magnetic field strength. Pigeon inner ears have previously been implicated in the ability of these animals to navigate using geomagnetic fields, through electrophysiological studies. It is found that the

Detonation nanodiamond (DND) is the smallest class of diamond nanocrystal capable of hosting various color centers with a size akin to molecular pores. Their negatively charged nitrogen-vacancy center (NV⁻) is a versatile tool for sensing a wide range of physical and even chemical parameters at the nanoscale. The NV⁻ is, therefore, attracting interest as the smallest quantum sensor in biological research. Nonetheless, recent NV⁻ enhancement in DND has yet to yield sufficient fluorescence per particle, leading to efforts to incorporate other group-IV color centers into DND. An example is adding a silicon dopant to the explosive mixture to create negatively charged silicon-vacancy centers (SiV⁻). In this paper, we report on efficient observation (∼50% of randomly selected spots) of the characteristic optically detected magnetic resonance (ODMR) NV⁻ signal in silicon-doped DND (Si-DND) subjected to boiling acid surface cleaning. The NV⁻ concentration is estimated by continuous-wave electron spin resonance spectroscopy to be 0.35 ppm without the NV⁻ enrichment process. A temperature sensitivity of 0.36 K/√HZ in an NV⁻ ensemble inside an aggregate of Si-DND is achieved via the ODMR-based technique. Transmission electron microscopy survey reveals that the Si-DNDs core sizes are ∼11.2 nm, the smallest among the nanodiamond’s temperature sensitivity studies. Furthermore, temperature sensing using both SiV⁻ (all-optical technique) and NV⁻ (ODMR-based technique) in the same confocal volume is demonstrated, showing Si-DND’s multimodal temperature sensing capability. The results of the study thereby pave a path for multi-color and multimodal biosensors and for decoupling the detected electrical field and temperature effects on the NV⁻ center.

This project aims to investigate the emission currents produced from nitrogen-doped dia- mond samples terminated with oxygen and lithium, to develop our understanding of such a material for use as an emitter surface in a thermionic energy converter (TEC). Thermionic devices offer clean, renewable energy generation from a device with no moving parts thus a large potential for device efficiency, such a device could be revolutionary for electricity gen- eration using solar power, or for clean hydrogen production from electrolysis. TECs could also be used for space-based solar power or energy generation for space travel due to the high physical and radiation hardness of diamond. For an effective TEC device, the semicon- ductor emitter surface must exhibit a negative electron affinity (NEA) for electron emission, as well as a low work function (WF) to reduce the operating temperatures of such a thermal device. Nitrogen is a deep-level electron donor when used as a diamond dopant, it easily incorpo- rates into the diamond lattice through substitutional sites. Lithium terminations have been studied both theoretically and experimentally to both induce an NEA and to reduce the work function by inducing dipoles on the surface of the diamond films, altering the semi- conductor’s band structure through electrostatic band bending.1,2,3 Oxygenation has shown to increase the bond strength of lithium to the surface as well as that of the surface dipoles, further reducing the WF.2,4,2 Diamond films have been grown using chemical vapour deposition (CVD) in nitrogen-rich environments, the effects of changing nitrogen flow rates within the gaseous growth mixture have been investigated in terms of sample quality and electronic properties of the resulting sample. Oxygenation will be used to increase the stability of the terminated lithium surface as well as to further reduce the

A large-scale quantum network, where many nodes are connected via entanglement and can share and process quantum information, will allow applications that are now unattainable. While some are known, ranging from distributed quantum computing to enhanced quantum sensing and quantum communication, the full potential of such a fundamentally new technology is yet to be discovered. Color centers in diamond, with their excellent optical properties, long spin coherence times, and versatile control over local nuclear spins, are a leading platform for building quantum network nodes and recently allowed crucial proof-of-principle experiments. Going beyond experiments and towards a large and functional network requires faster entanglement generation and a scalable architecture. Integration of color centers in nanophotonic structures paves the way to solving these challenges, enhancing the interface between the spins and photons that carry quantum information across the network. Furthermore, combining diamond nanophotonic devices with integrated photonic and electronic circuits is a promising way to realize a large-scale quantum system. This thesis is about integrated spin-photon interfaces in diamonds and how to generate entanglement between them and includes experimental and theoretical results toward this goal. First, we introduce the Group-IV color centers in diamond, which thanks to their symmetry properties are robust against electric field noise and compatible with integration in nano-scale structures. Focusing on the tin-vacancy (SnV) center, we discuss the main features and effects that play a role in its use as a spin-photon interface. We then present experimental results going from the fabrication and characterization of bulk diamond samples with SnV centers to the integration in nanophotonic waveguides, where we show stable and coherent optical lines and measure the extinction of the transmission signal caused by a single SnV center with contrast up to 35%., QID/Hanson Lab

The sponge-like biomineralized calcite materials found in echinoderm skeletons are of interest in terms of both structure formation and biological function. Despite their crystalline atomic structure, they exhibit curved interfaces that have been related to known triply periodic minimal surfaces. Here, we investigate the endoskeleton of the sea urchin Cidaris rugosa that has long been known to form a microstructure related to the Primitive surface. Using X-ray tomography, we find that the endoskeleton is organized as a composite material consisting of domains of bicontinuous microstructures with different structural properties. We describe, for the first time, the co-occurrence of ordered single Primitive and single Diamond structures and of a disordered structure within a single skeletal plate. We show that these structures can be distinguished by structural properties including solid volume fraction, trabeculae width and, to a lesser extent, interface area and mean curvature. In doing so, we present a robust method that extracts interface areas and curvature integrals from voxelized datasets using the Steiner polynomial for parallel body volumes. We discuss these very large-scale bicontinuous structures in the context of their function, formation and evolution.

The sponge-like biomineralized calcite materials found in echinoderm skeletons are of interest in terms of both structure formation and biological function. Despite their crystalline atomic structure, they exhibit curved interfaces that have been related to known triply periodic minimal surfaces. Here, we investigate the endoskeleton of the sea urchin Cidaris rugosa that has long been known to form a microstructure related to the Primitive surface. Using X-ray tomography, we find that the endoskeleton is organized as a composite material consisting of domains of bicontinuous microstructures with different structural properties. We describe, for the first time, the co-occurrence of ordered single Primitive and single Diamond structures and of a disordered structure within a single skeletal plate. We show that these structures can be distinguished by structural properties including solid volume fraction, trabeculae width and, to a lesser extent, interface area and mean curvature. In doing so, we present a robust method that extracts interface areas and curvature integrals from voxelized datasets using the Steiner polynomial for parallel body volumes. We discuss these very large-scale bicontinuous structures in the context of their function, formation and evolution.

Quantum sensing aims to further our understanding of the natural world and support an upcoming technological revolution by exploiting quantum properties or systems to exceed the performance of classical sensing. Owing to their convenient modes of operation and strong room temperature quantum properties, optically active spin defects hosted within solid state materials have come to prominence as one of the foremost tools of choice in this landscape. Many applications now aim to leverage dense ensembles of such defects to boost measurement sensitivity or scale up, which places greater emphasis on the quality of the host material and sensor production methods since cherry-picking individual defects is no longer an option. The prototypical example of such a defect is the nitrogen-vacancy (NV) centre in diamond, which exhibits remarkable room temperature spin coherence, bestowed upon it by diamond's material properties. In this thesis, we first look at optimising the production of NV ensembles for quantum sensing, aiming to efficiently and cost-effectively produce sensors capable of performing high sensitivity measurements in two key regimes that will be central to the experimental applications explored later. The topics examined are hyperpolarisation of a nuclear spin ensemble on the diamond surface through coupling to an ultra-near-surface NV layer, and investigating the properties of a van der Waals antiferromagnet through widefield NV microscopy. The demands placed on the NV layer for these applications are diverse from one another, with charge stability and quantum coherence properties being vital for the former, and the ability to scalably and reproducibly create layers of known thickness crucial to the latter. In light of these studies, we finally consider whether a different spin system housed within an entirely separate materials system, the boron-vacancy defect in hexagonal boron nitride, may be a suitable alternative to the well-established NV diamond system.

A new diamond anvil cell experimental approach has been implemented at the European x-ray Free Electron Laser, combining pulsed laser heating with MHz x-ray diffraction. Here, we use this setup to determine liquidus temperatures under extreme conditions, based on the determination of time-resolved crystallization. The focus is on a Fe-Si-O ternary system, relevant for planetary cores. This time-resolved diagnostic is complemented by a finite-element model, reproducing temporal temperature profiles measured experimentally using streaked optical pyrometry. This model calculates the temperature and strain fields by including (i) pressure and temperature dependencies of material properties, and (ii) the heat-induced thermal stress, including feedback effect on material parameter variations. Making our model more realistic, these improvements are critical as they give 7000 K temperature differences compared to previous models. Laser intensities are determined by seeking minimal deviation between measured and modeled temperatures. Combining models and streak optical pyrometry data extends temperature determination below detection limit. The presented approach can be used to infer the liquidus temperature by the appearance of SiO 2 diffraction spots. In addition, temperatures obtained by the model agree with crystallization temperatures reported for Fe-Si alloys. Our model reproduces the planetary relevant experimental conditions, providing temperature, pressure, and volume conditions. Those predictions are then used to determine liquidus temperatures at experimental timescales where chemical migration is limited. This synergy of novel time-resolved experiments and finite-element modeling pushes further the interpretation capabilities in diamond anvil cell experiments.

This research aims to develop techniques for creating robust, hermetic joints and encapsulated structures using gold (Au) braze alloys and ceramic substrates for electronics and implantable medical devices. A major challenge is the poor wetting and adhesion typically observed between Au brazes and ceramics due to interfacial reactions and surface oxides. Without suitable adhesion layers, weak boundary joints prone to failure may result. We investigate processing methods involving thin film deposition, adhesion layer metals, brazing parameters, and joint analysis to overcome these adhesion issues with Au brazing on ceramics. A priority application is creating long-lasting, leak-proof packages for electronics in medical implants, which must meet strict encapsulation requirements for human use. Diamond demonstrates exceptional implantation lifetimes owing to outstanding biostability and biocompatibility but cannot be welded. One alternative is active braze alloys, containing carbide-forming elements that chemically bond to the diamond upon melting. However, biocompatible gold active braze alloys (Au-ABA) exhibit very poor wetting on diamond. I demonstrate that molybdenum (Mo) and niobium (Nb) interlayers significantly improve Au-ABA wetting, enabling excellent penetration into surface features. Optimal recipes for interlayer fabrication are determined, facilitating complex microstructures, hermetic electrical feedthroughs, and robust bonds. In laser-grooved diamond circuit boards, residual metal contamination resistant to etching and polishing was found to electrically short features after depositing Mo/Nb adhesion layers and Au-ABA brazing. Here, I reported an optimised reactive ion etching (RIE) process to remove this contamination and isolate fine circuit board features. Elemental and electrical testing verifies complete contaminant removal and restoration of electrically insulating diamond surface properties after RIE.

Although theoretical investigations indicate that the successful combination of graphene and diamond would give interesting properties, only a limited number of reports dealing with the subject have been published. Here, we present a rapid thermal process (RTP) which involves nickel (Ni) as metal catalyst for a direct growth of graphene on diamond at a temperature of 1073 K for 60 s. This process operates with a combination of a lower temperature and for a shorter duration than what has previously been reported. Thin Ni films of different thicknesses were deposited on top of (100) single-crystalline diamond. After RTP, the coverage of monolayer graphene was found to be around 20% shown by the intensity ratio between the 2D- and G-peak using Raman spectroscopy on 50 nm thick Ni films. In addition, x-ray photoelectron spectroscopy and atomic force microscopy analysis were conducted. For electrical characterization, Hall-effect measurements were performed at temperatures between 80 and 360 K.

Although theoretical investigations indicate that the successful combination of graphene and diamond would give interesting properties, only a limited number of reports dealing with the subject have been published. Here, we present a rapid thermal process (RTP) which involves nickel (Ni) as metal catalyst for a direct growth of graphene on diamond at a temperature of 1073 K for 60 s. This process operates with a combination of a lower temperature and for a shorter duration than what has previously been reported. Thin Ni films of different thicknesses were deposited on top of (100) single-crystalline diamond. After RTP, the coverage of monolayer graphene was found to be around 20% shown by the intensity ratio between the 2D- and G-peak using Raman spectroscopy on 50 nm thick Ni films. In addition, x-ray photoelectron spectroscopy and atomic force microscopy analysis were conducted. For electrical characterization, Hall-effect measurements were performed at temperatures between 80 and 360 K.

The development of electrodes for the electrical modulation of cell activity has become a research topic of increasing interest, due to an ever-growing list of applications. These include deep brain stimulation for neurodegenerative disorders such as Parkinson’s and Alzheimer’s disease; implantable bionic devices such as the Cochlear ear implant and bionic eye; and promoting cell growth for wound healing or tissue engineering. Electrical stimulation is conventionally achieved by delivering current from an external power source through metallic electrodes to the target biological tissue. However, these types of electrodes have drawbacks. For instance, they typically require cumbersome and invasive wiring, while the stimulating spatial resolution is limited by current spreading. One attractive alternative technique is light-based stimulation, which offers wireless and scalable targeting of cells with superior spatial precision. In particular, light-sensitive electrode materials can be used to transduce light into an electrical stimulus to excite nearby cells. Nitrogen-doped ultrananocrystalline diamond (N-UNCD) is a promising material for this technique, possessing a highly attractive combination of properties including high chemical inertness, durability, conductivity, and biocompatibility. In addition, it has also been shown to produce a photoresponse using near-infrared light, which offers greater optical penetration in biological tissue than shorter wavelengths. In this thesis, we optimise and characterise N-UNCD electrodes for light-based cell stimulation, and then demonstrate their use in the modulation of stem cell cultures. To achieve this, we tested the effect of different chemical surface treatments on the stimulating performance of the N-UNCD electrodes, measured by the capacitance and photoresponse. Of these treatment methods, we found that annealing N-UNCD in oxygen ambient produced dramatically improved properties, with the capacitance and photoresponse

Although theoretical investigations indicate that the successful combination of graphene and diamond would give interesting properties, only a limited number of reports dealing with the subject have been published. Here, we present a rapid thermal process (RTP) which involves nickel (Ni) as metal catalyst for a direct growth of graphene on diamond at a temperature of 1073 K for 60 s. This process operates with a combination of a lower temperature and for a shorter duration than what has previously been reported. Thin Ni films of different thicknesses were deposited on top of (100) single-crystalline diamond. After RTP, the coverage of monolayer graphene was found to be around 20% shown by the intensity ratio between the 2D- and G-peak using Raman spectroscopy on 50 nm thick Ni films. In addition, x-ray photoelectron spectroscopy and atomic force microscopy analysis were conducted. For electrical characterization, Hall-effect measurements were performed at temperatures between 80 and 360 K.

We numerically explore synthetic crystal diamond for realizing novel light sources in ranges which are up to now difficult to achieve with other materials, such as sub-10-fs pulse durations and challenging spectral ranges. We assess the performance of on-chip diamond waveguides for controlling light generation by means of nonlinear soliton dynamics. The considered silica-embedded diamond waveguide model exhibits two zero-dispersion points, delimiting an anomalous dispersion range that exceeds an octave. Various propagation dynamics, including supercontinuum generation by soliton fission, can be realized in diamond photonics. In contrast to usual silica-based optical fibers, where such processes occur on the scale of meters, in diamond millimeter-scale propagation distances are sufficient. Unperturbed soliton-dynamics prior to soliton fission allow identifying a pulse self-compression scenario that promises record-breaking compression factors on chip-size propagation lengths.

Crop production is becoming an increasing challenge as the global population grows and the climate changes. Modern cultivated crop species are selected for productivity under optimal growth environments and have often lost genetic variants that could allow them to adapt to diverse, and now rapidly changing, environments. These genetic variants are often present in their closest wild relatives, but so are less desirable traits. How to preserve and effectively utilize the rich genetic resources that crop wild relatives offer while avoiding detrimental variants and maladaptive genetic contributions is a central challenge for ongoing crop improvement. This Essay explores this challenge and potential paths that could lead to a solution.

Although theoretical investigations indicate that the successful combination of graphene and diamond would give interesting properties, only a limited number of reports dealing with the subject have been published. Here, we present a rapid thermal process (RTP) which involves nickel (Ni) as metal catalyst for a direct growth of graphene on diamond at a temperature of 1073 K for 60 s. This process operates with a combination of a lower temperature and for a shorter duration than what has previously been reported. Thin Ni films of different thicknesses were deposited on top of (100) single-crystalline diamond. After RTP, the coverage of monolayer graphene was found to be around 20% shown by the intensity ratio between the 2D- and G-peak using Raman spectroscopy on 50 nm thick Ni films. In addition, x-ray photoelectron spectroscopy and atomic force microscopy analysis were conducted. For electrical characterization, Hall-effect measurements were performed at temperatures between 80 and 360 K.

© 1999 IOP Publishing Ltd. This work has been funded by the European Community through programme TMR (project ERBFMRXCT960050). The authors wish to thank Dr Tomás González from the University of Salamanca for his helpful comments., This paper presents a procedure to improve the algorithm of Sangiorgi, Ricco and Venturi for the calculation of the time of flight in Monte Carlo simulations. The method is used to efficiently optimize the step function in which the total scattering probability is discretized. The optimization criterion suggested in this work can reduce the self-scattering events to less than 30% in a fairly wide range of temperatures, applied fields and doping levels. Different examples are presented to illustrate the advantages of the method., European Community through programme TMR, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2006 The American Physical Society. We acknowledge financial support from MCyT (Spain) under Grants No. MAT2003-08627-C0201 and No. FIS2005-0747. A. M. thanks the program ‘‘Ramón y Cajal.’’ R. C. thanks ‘‘Comunidad de Madrid’’ and ‘‘Fondo Social Europeo.’’ Part of this work was performed at the Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland. STM images have been analyzed using WSxM software from Nanotec., We report an investigation on the properties of 0.33 ML of Sn on Ge(111) at temperatures down to 5 K. Low-energy electron diffraction and scanning tunneling microscopy show that the (3 x 3) phase formed at similar to 200 K, reverts to a new (root 3 x root 3)R30 degrees phase below 30 K. The vertical distortion characteristic of the (3 x 3) phase is lost across the phase transition, which is fully reversible. Angle-resolved photoemission experiments show that, concomitantly with the structural phase transition, a metal-insulator phase transition takes place. The (root 3 x root 3)R30 degrees ground state is interpreted as the formation of a Mott insulator for a narrow half-filled band in a two-dimensional triangular lattice., MCyT (Spain), Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

©2015 AIP Publishing LLC. This work has been supported by MINECO (Project Nos. MAT 2012-31959 and CSD 2009-00013). J.B. acknowledges the financial support from Universidad Complutense de Madrid., The mechanical resonance behavior of as-grown In_2O_3 microrods has been studied in this work by in-situ scanning electron microscopy (SEM) electrically induced mechanical oscillations. Indium oxide microrods grown by a vapor–solid method are naturally clamped to an aluminum oxide ceramic substrate, showing a high quality factor due to reduced energy losses during mechanical vibrations. Quality factors of more than (10)^5 and minimum detectable forces of the order of (10)^(16) N/Hz^(1/2) demonstrate their potential as mechanical microresonators for real applications. Measurements at low- vacuum using the SEM environmental operation mode were performed to study the effect of extrinsic damping on the resonators behavior. The damping coefficient has been determined as a function of pressure., Ministerio de Economía y Competitividad (MINECO), Universidad Complutense de Madrid, Depto. de Física Teórica, Fac. de Ciencias Físicas, TRUE, pub

We investigate discharge contraction in a microwave plasma at sub-atmospheric pressure, operating in CO2 and CO2/CH4 mixtures. The rise of the electron number density with plasma contraction intensifies the gas heating in the core of the plasma. This, in turn, initiates fast core-periphery transport and defines the rate of thermal chemistry over plasma chemistry. In this context, power concentration describes the overall mechanism including plasma contraction and chemical kinetics. In a complex chemistry such as dry reforming of methane, transport of reactive species is essential to define the performance of the reactor and achieve the desired outputs. Thus, we couple experimental observations and thermodynamic calculations for model validation and understanding of reactor performance. Adding CH4 alters the thermodynamic properties of the mixture, especially the reactive component of the heat conductivity. The increase in reactive heat conductivity increases the pressure at which plasma contraction occurs, because higher rates of gas heating are required to reach the same temperature. In addition, we suggest that the predominance of heat conduction over convection is a key condition to observe the effect of heat conductivity on gas temperature.

Within our increasingly digital world, there is a demand to integrate electronics into every industry to take advantage of applications in communication, optimization, and artificial intelligence. Relatively untapped areas for electronics implementation are the extreme environments where high temperatures (>300°C) are present. These environments are common within energy, automotive, and aerospace industry es. Current high temperature technologies limit reliable use of electronics to ~200°C. Emerging technologies, such as transient liquid phase (TLP) bonding, copper sintering, and thick films, have not yet demonstrated resilient operation above 300°C. Possessing various remarkable properties, diamond is a promising material that can be used in manufacturing electronic devices operable well above 500°C. Graphene and graphite additionally can serve as conductive material for circuitry or other electronic elements. The compatibility and versatility of these three materials demonstrate the potential for robust, all-carbon electronics for high temperature applications. Chemical vapor deposition (CVD), the predominant method of synthesizing diamond for electronics, involves very costly, long processes at extreme temperatures. A relatively underdeveloped, alternative method utilizes the pyrolysis of polymer precursors into diamond. This study aims to further explore this method using Poly(naphthalene-co-hydridocarbyne) (PNHC). The polymer synthesis, processing, and pyrolysis have been performed here, and the process parameters and outcomes at each step have been documented. Native graphite and graphene growth on diamond surfaces allows for the integration of conductive material on insulating diamond. Four known methods of diamond graphitization, assisted with the metal catalysts nickel, copper, and iron, have also been applied to support the fabrication of carbon-based electronics. Ultimately in this study, the synthesis of diamond has been unsuccessful, but multi-layer gra

Intriguing photophysical properties of color centers in diamond make them ideal candidates for many applications from imaging and sensing to quantum networking. In the first part of this work, we have studied the silicon vacancy (SiV) centers in diamond for nanoscale imaging applications. We showed that these centers are promising fluorophores for Stimulated Emission Depletion (STED) microscopy, owing to their photostable, near-infrared emission and favorable photophysical properties. In the second part, we built a femtotesla Radio-Frequency (RF) magnetometer based on the diamond nitrogen vacancy (NV) centers and magnetic flux concentrators. We used this sensor to remotely detect Nuclear Quadrupole Resonance (NQR) signals from room-temperature powders. Finally, we outline future directions to further study the SiV centers for some potential applications in salable quantum networks and localization-based microscopy techniques.

This dissertation explores the development and application of diamond color centers, specifically the silicon-vacancy (SiV) and nitrogen-vacancy (NV) centers, in super-resolution microscopy and magnetic imaging techniques. It demonstrates the potential of SiV centers as photostable fluorophores in stimulated emission depletion (STED) microscopy, with a resolution of approximately 90 nm. The research also presents a method for nanoscale magnetic microscopy using NV centers by combining charge state depletion (CSD) microscopy with optically detected magnetic resonance (ODMR) to image magnetic fields produced by 30 nm iron-oxide nanoparticles. The individual magnetic feature width reaches ~100 nm while resolving magnetic field patterns from nanoparticles spaced as close as ~190 nm. Despite some limitations, these findings highlight the versatility and potential of diamond color centers in advancing super-resolution microscopy and nanoscale magnetic imaging.

An effective structural transformation from an sp3-hybridised diamond into an sp2-hybridised graphite as well as precisely micromachining the diamond crystal with an acceptable precision and accuracy at the micro- and/or nano- scale can only be achieved with a careful application of well-tuned ultrashort femtosecond (fs)-laser pulses, thus avoiding the generation of thermal stresses and the resultant thermal damage of the surrounding material, which is the main problem encountered in the conventional laser processing. An ultrashort pulsed laser with a pulse duration of 30 fs has been used for the first time in this research project to minimize the heat diffusion into the lattice as the material processing with sub-50 fs pulses is driven predominantly by the photoionization of electrons without the heat transfer to the surrounding material. This thesis aims to nonthermally transform the surface of diamond into an aromatic sp2 graphitic phase with high crystallinity as well as to micromachine the surface of diamond with high machined surface quality and high volumetric processing efficiency. [...], Thesis (PhD Doctorate), Doctor of Philosophy (PhD), School of Eng & Built Env, Science, Environment, Engineering and Technology, Full Text

Spin-waves, the propagation of circular preccession of spins, have been offered as a way to replace electric currents as information carriers. The overwhelming advantage being the lack of moving charges and Ohmic losses. In this context, the search for an efficient method of detection of becomes crucial. Nitrogen vacancy centers in diamond offer a highly sensitive and effective solution. These diamond lattice defects have quan- tum and optical features allowing them to be used to quantify the surrounding magnetic field. This project is composed of a theoretical study of spin waves followed by an experimental section where AC magnetometry is tried out as a detection method. First the computations for the dispersion relation of spin waves in a ferro- magnetic material where done. A simplified version assuming homogeneity in one direction is presented and then an expansion considering a wave mode of the first order in the previously constant direction is attempted. An analysis on the efficiency of spin wave generation outlines the conditions on the wavelength and the po- larisation needed to correctly drive spin waves while being able to measure them using NV centers. Then the experimental setup and steps of AC magnetometry are layed out. The results of a measurement are shown and are in alignment with the theoretical predictions, proving this to be a valid method., Applied Mathematics

The hot-filament chemical vapor deposition (HF-CVD) method is widely used for the synthesis of thin films of polycrystalline diamond. These films are used in a broad range of applications, such as coating material on cutting tools, heat spreaders, and electrochemical sensors. HF-CVD offers some unique advantages in terms of simplicity, low equipment cost, and scalability. Recently, a novel HF-CVD system has been designed and built at dept. PME (TU Delft), which should enable diamond deposition over relatively large substrate areas (i.e., two-inch wafers) by employing an array of multiple straight metallic filaments. However, the use of this setup so far has been primarily restricted due to the premature failure of the tungsten filaments. During the high-temperature chemical vapor deposition process, the filaments undergo large deformations due to carburization, leading to the formation of brittle metal carbides. In the initial configuration, the filaments were placed in a custom-made clamping device, obstructing their ability to expand and contract freely, resulting in residual mechanical stresses that caused premature failure of the filaments after cooling down. To enable diamond growth in this setup, a new approach is needed. In this research, different placements of the filaments within the existing clamping device were tested to determine the optimized placement that ensures a longer filament lifespan. Additionally, a preliminary experimental parameter study was performed to investigate the effects of different deposition parameters (i.e., filament-substrate distance, stage temperature, and methane concentration) on the diamond growth on Si (100) substrates. The optimized filament placement was achieved by simply resting the tungsten filament on both electrodes without additional fixations. In this configuration, the filaments could be used for multiple interrupted deposition runs, and even after 162 hours of usage, the filaments remain, Mechanical Engineering

Although theoretical investigations indicate that the successful combination of graphene and diamond would give interesting properties, only a limited number of reports dealing with the subject have been published. Here, we present a rapid thermal process (RTP) which involves nickel (Ni) as metal catalyst for a direct growth of graphene on diamond at a temperature of 1073 K for 60 s. This process operates with a combination of a lower temperature and for a shorter duration than what has previously been reported. Thin Ni films of different thicknesses were deposited on top of (100) single-crystalline diamond. After RTP, the coverage of monolayer graphene was found to be around 20% shown by the intensity ratio between the 2D- and G-peak using Raman spectroscopy on 50 nm thick Ni films. In addition, x-ray photoelectron spectroscopy and atomic force microscopy analysis were conducted. For electrical characterization, Hall-effect measurements were performed at temperatures between 80 and 360 K.

Nature employs an impressive range of topologically complex ordered nanostructures that occur in various forms in both natural and synthetic materials. A particular class of these exhibits negative curvature and forms periodic saddle-shaped surfaces in three dimensions. Unlike pattern formation on flat or positively curved surfaces like spherical systems, the understanding of patterning on such surfaces is highly complicated due to the structures being intrinsically intertwined in three dimensions. We present a new method for visualisation and analysis of patterns on triply periodic negatively curved surfaces by mapping to two-dimensional hyperbolic space analogous to spherical projections in cartography thus effectively creating a more accessible "hyperbolic map" of the pattern. Specifically, we exemplify the method via the simplest triply periodic minimal surfaces: the Primitive, Diamond, and Gyroid in their universal cover along with decorations from a soft materials, whose structures involve decorations of soft matter on negatively curved surfaces, not necessarily minimal.

Solid carbon deposition is a persistent challenge in dry reforming of methane (DRM), affecting both classical and plasma-based processes. In this work, we use a microwave plasma in reverse vortex flow configuration to overcome this issue in CO2/CH4 plasmas. Indeed, this configuration efficiently mitigates carbon deposition, enabling operation even with pure CH4 feed gas, in contrast to other configurations. At the same time, high reactor performance is achieved, with CO2 and CH4 conversions reaching 33% and 44% respectively, at an energy cost of 14 kJ L-1 for a CO2 : CH4 ratio of 1 : 1. Laser scattering and optical emission imaging demonstrate that the shorter residence time in reverse vortex flow lowers the gas temperature in the discharge, facilitating a shift from full to partial CH4 pyrolysis. This underscores the pivotal role of flow configuration in directing process selectivity, a crucial factor in complex chemistries like CO2/CH4 mixtures and very important for industrial applications.Our work demonstrates that solid carbon-free conversion of green-house gases into value-added compounds is possible by changing the gas flow configuration in a microwave plasma, making significant strides in green chemistry.

Liberia intends to harness the development potential of artisanal mining through formalization. However, there are several obstacles that the country needs to overcome for it to succeed. The existing literature provides evidence on the challenges faced by miners and local authorities, but fails to make a distinction between different types of activities. This study sets out to identify differences in formalization patterns across the two largest artisanal sectors, namely gold and diamond mining. Drawing on an extensive survey of 231 communities and 174 mines in Gbarpolu County, we spatially match mining sites to their nearest license recorded in the country's cadastre. To do so, we consider both distance to licenses and concentration of mines around titles before loosening the definition of formality by exploring town chiefs’ perceptions. We complement our spatial analysis with qualitative insights into miners’ views on the challenges and opportunities of artisanal gold versus diamond mining. Our findings show that artisanal diamond mines are more likely to fall under what we define as an “umbrella of formality” compared to gold mines. We explain this difference through geology, but also the history and perceptions of the respective minerals. Against this backdrop, we question the effectiveness of formalization as it is currently conceived in Liberia. We argue that distinguishing between artisanal mining sectors is important to understand the different sets of incentives and constraints that miners face. This, in turn, is key to the design of tailored and effective formalization policies.

In this thesis we describe the development of a kinetic Monte Carlo model for the growth of diamond using chemical vapour deposition. The implemented growth model, which can simulate minutes of growth for systems of more than 10,000 carbons, is parametrised by growth-condition inputs taken from detailed modelling and experiment. It is the first of its kind to include the rapid etching of isolated species in combination with CHx migration. The bespoke FORTRAN simulation framework is used to investigate the accuracy of the implemented gas-surface reactions and the kinetics of potential growth mechanisms. In the first part of this thesis, the model was benchmarked and parametrised with reference to theoretical and experimental literature. An energy barrier to isolated-carbon etching of approximately 35 kJ mol−1, which produced realistic growth behaviour, was in agreement with quantum mechanical calculations. Predictions of growth rates and film roughness as a function of growth condition were largely in agreement with theoretical and experimental literature, although behaviour under microwave-reactor conditions suggested the approximated concentrations of CHx, H or H2 species were inaccurate, or that 2-carbon species play a key role in growth. The formation of deep {111} facets indicate that trough incorporation mechanisms require further investigation. In the second part of this thesis, the underlying mechanisms behind the observed formation of domains of aligned C–C dimers on the hydrogenated {100} surface were investigated. Passive alignment of forming dimers, driven by favourable energetics had no effect on long-range alignment; the concentration of adjacent carbon radicals was too low. Etching of dimers isolated on the surface also had no effect on alignment, or the formation of domains of dimers. The inclusion of both isolated-carbon and isolated-dimer etching processes together resulted in the reduction of surface pits, although growth-rate pre

Domestic and service robots have the potential to transform industries such as health care and small-scale manufacturing, as well as the homes in which we live. However, due to the overwhelming variety of tasks these robots will be expected to complete, providing generic out-of-the-box solutions that meet the needs of every possible user is clearly intractable. To address this problem, robots must therefore not only be capable of learning how to complete novel tasks at run-time, but the solutions to these tasks must also be informed by the needs of the user. In this letter we demonstrate how behaviour trees, a well established control architecture in the fields of gaming and robotics, can be used in conjunction with natural language instruction to provide a robust and modular control architecture for instructing autonomous agents to learn and perform novel complex tasks. We also show how behaviour trees generated using our approach can be generalised to novel scenarios, and can be re-used in future learning episodes to create increasingly complex behaviours. We validate this work against an existing corpus of natural language instructions, demonstrate the application of our approach on both a simulated robot solving a toy problem, as well as two distinct real-world robot platforms which, respectively, complete a block sorting scenario, and a patrol scenario.

The interaction between acoustic phonons and electrons in diamond has been investigated by comparing state-of-the-art time-of-flight drift velocity measurements with Monte Carlo simulations. We use a multivariable anisotropic description of acoustic deformation potential scattering. The phonon-electron interaction is the limiting factor for the carrier mobility in ultrapure single crystal diamond. Hence, having a correct description is necessary for both device simulations and for predicting the maximum device performance. The experiments were performed at low temperature and using ultrapure diamond to minimize the influence of other scattering sources. The electronic valley polarization in diamond at low temperatures enables determination of both uniaxial and dilatation deformation potentials in the same experiment. The uniaxial and dilatation deformation potentials are found to be 18.5±0.2 and −5.7±0.3 eV, respectively.

The interaction between acoustic phonons and electrons in diamond has been investigated by comparing state-of-the-art time-of-flight drift velocity measurements with Monte Carlo simulations. We use a multivariable anisotropic description of acoustic deformation potential scattering. The phonon-electron interaction is the limiting factor for the carrier mobility in ultrapure single crystal diamond. Hence, having a correct description is necessary for both device simulations and for predicting the maximum device performance. The experiments were performed at low temperature and using ultrapure diamond to minimize the influence of other scattering sources. The electronic valley polarization in diamond at low temperatures enables determination of both uniaxial and dilatation deformation potentials in the same experiment. The uniaxial and dilatation deformation potentials are found to be 18.5±0.2 and −5.7±0.3 eV, respectively.

The interaction between acoustic phonons and electrons in diamond has been investigated by comparing state-of-the-art time-of-flight drift velocity measurements with Monte Carlo simulations. We use a multivariable anisotropic description of acoustic deformation potential scattering. The phonon-electron interaction is the limiting factor for the carrier mobility in ultrapure single crystal diamond. Hence, having a correct description is necessary for both device simulations and for predicting the maximum device performance. The experiments were performed at low temperature and using ultrapure diamond to minimize the influence of other scattering sources. The electronic valley polarization in diamond at low temperatures enables determination of both uniaxial and dilatation deformation potentials in the same experiment. The uniaxial and dilatation deformation potentials are found to be 18.5±0.2 and −5.7±0.3 eV, respectively.

Extending the limit of charge-carrier mobility in semiconductors has been a long-standing pursuit in material science and its applications. Herein, we investigate the electron mobility via cyclotron resonance in undoped diamond under continuous-wave photoexcitation, whereby the density of charge carriers can be reduced to 108cm−3 or 1/10 of the previous detection limit [K. Konishi et al., Appl. Phys. Lett. 117, 212102 (2020)]. For low-density electrons, which obviate the effects of carrier-carrier scattering as a broadening mechanism, we observe an extraordinarily narrow cyclotron resonance spectrum. After correcting for the microwave power broadening, the highest intrinsic mobility value of 100×106 cm2V−1s−1 is obtained at 3 K, which is a 16-fold increase of the mobility compared with the previous record in diamond. Our result is beneficial for the design and application of diamond radiation detectors implemented for their practical use at cryogenic temperatures.

Transistors operating at high frequencies are the basic building blocks of millimeter-wave communication and sensor systems. The high charge-carrier mobility and saturation velocity in graphene can open way for ultra-fast field-effect transistors with a performance even better than what can be achieved with III-V-based semiconductors. However, the progress of high-speed graphene transistors has been hampered by fabrication issues, influence of adjacent materials, and self-heating effects. Here, we report on the improved performance of graphene field-effect transistors (GFETs) obtained by using a diamond substrate. An extrinsic maximum frequency of oscillation fmax of up to 54 GHz was obtained for a gate length of 500 nm. Furthermore, the high thermal conductivity of diamond provides an efficient heat-sink, and the relatively high optical phonon energy of diamond contributes to an increased charge-carrier saturation velocity in the graphene channel. Moreover, we show that GFETs on diamond exhibit excellent scaling behavior for different gate lengths. These results promise that the GFET-on-diamond technology has the potential of reaching sub-terahertz frequency performance.

In this thesis we describe the development of a kinetic Monte Carlo model for the growth of diamond using chemical vapour deposition. The implemented growth model, which can simulate minutes of growth for systems of more than 10,000 carbons, is parametrised by growth-condition inputs taken from detailed modelling and experiment. It is the first of its kind to include the rapid etching of isolated species in combination with CHx migration. The bespoke FORTRAN simulation framework is used to investigate the accuracy of the implemented gas-surface reactions and the kinetics of potential growth mechanisms. In the first part of this thesis, the model was benchmarked and parametrised with reference to theoretical and experimental literature. An energy barrier to isolated-carbon etching of approximately 35 kJ mol−1, which produced realistic growth behaviour, was in agreement with quantum mechanical calculations. Predictions of growth rates and film roughness as a function of growth condition were largely in agreement with theoretical and experimental literature, although behaviour under microwave-reactor conditions suggested the approximated concentrations of CHx, H or H2 species were inaccurate, or that 2-carbon species play a key role in growth. The formation of deep {111} facets indicate that trough incorporation mechanisms require further investigation. In the second part of this thesis, the underlying mechanisms behind the observed formation of domains of aligned C–C dimers on the hydrogenated {100} surface were investigated. Passive alignment of forming dimers, driven by favourable energetics had no effect on long-range alignment; the concentration of adjacent carbon radicals was too low. Etching of dimers isolated on the surface also had no effect on alignment, or the formation of domains of dimers. The inclusion of both isolated-carbon and isolated-dimer etching processes together resulted in the reduction of surface pits, although growth-rate pre

Current nuclear energy ontologies are known to lack a common vocabulary to formally verify nuclear energy data relationships for modeling system behaviors. Idaho National Laboratory (INL) developed the Data Integration Aggregated Model and Ontology for Nuclear Deployment (DIAMOND) ontology to provide a standard vocabulary and taxonomy for identifying data relationships in nuclear energy system models. This thesis conducted an analysis of DIAMOND using a Spent Fuel Pool (SFP) Monterey Phoenix (MP) behavior model. The SFP MP behavior modeling application demonstrated components of and interactions among a spent fuel cooling pool and its environment. The MP behavior model demonstrated a viable approach for analyzing nuclear reactor system behavior consistent with DIAMOND and the ability to generate the exhaustive set of nuclear reactor cooling pool behavior scenarios. The results supported the ability of DIAMOND definitions to be used to organize and structure knowledge about SFP’s normal and off-normal behaviors. The SPF example showed the application of assets, actions, and triggers from DIAMOND to events and relationships in MP. Assets and actions were represented as MP events, and triggers were represented as precedence relations between MP events. This thesis research verified the DIAMOND ontology was implemented correctly in the model from data representative of operationally realistic behavior and the modeling results validated the MP behavior model was well constrained., Idaho National Lab, Civilian, Department of the Air Force, Approved for public release. Distribution is unlimited.

Machining of Aluminum can be complicated due to large amounts of adhesion and diffusion of the aluminum onto the cutting tool, causing effects such as built-up layers and built-up edges. This leads to poor surface finishes and can significantly affect the tool life. CVD diamond coated tools have shown to be a potential solution to this problem and is tested and analyzed as such in this thesis. CVD diamond coated inserts are tested and compared to uncoated cemented carbide inserts and Polycrystalline diamond tipped inserts, in milling, turning and in refined tribological methods. The workpiece material in both the machine tests and the tribological tests is a high strength aluminum of the name Alumec 89. The machine tests were performed for 5 and 60 seconds at three cutting speeds, 600, 900 and 1200 m/min, keeping other parameters constant. The cutting inserts, the chips and the generated workpiece surface are examined using LOM, SEM and EDS. In the refined tribological testing, a pin-turning tribometer is used, with pins of uncoated and coated (CVD diamond) cemented carbide pins. These are tested at 5 and 30 seconds at 600 and 1200 m/min, applying a constant force of 10 N. In addition, a friction test was performed to measure the friction of the uncoated and the CVD diamond coated cemented carbide. Like the cutting inserts, the used pins were examined in LOM and SEM. The results show that while a large amount of built-up layer and built-up edges gather when using uncoated cemented carbide tools, only minimal amounts can be detected on CVD diamond and PCD. It has also been shown that the reason for the reduced adhesion in the case of diamond tooling materials is most likely due to the lack of chemical interactions between the diamond and the aluminum. The friction of the CVD diamond material was shown to be lower compared to the cemented carbide. The surface finish generated by the different materials, was the best in the case of PCD while the CVD generated multiple

The interaction between acoustic phonons and electrons in diamond has been investigated by comparing state-of-the-art time-of-flight drift velocity measurements with Monte Carlo simulations. We use a multivariable anisotropic description of acoustic deformation potential scattering. The phonon-electron interaction is the limiting factor for the carrier mobility in ultrapure single crystal diamond. Hence, having a correct description is necessary for both device simulations and for predicting the maximum device performance. The experiments were performed at low temperature and using ultrapure diamond to minimize the influence of other scattering sources. The electronic valley polarization in diamond at low temperatures enables determination of both uniaxial and dilatation deformation potentials in the same experiment. The uniaxial and dilatation deformation potentials are found to be 18.5±0.2 and −5.7±0.3 eV, respectively.

Machining of Aluminum can be complicated due to large amounts of adhesion and diffusion of the aluminum onto the cutting tool, causing effects such as built-up layers and built-up edges. This leads to poor surface finishes and can significantly affect the tool life. CVD diamond coated tools have shown to be a potential solution to this problem and is tested and analyzed as such in this thesis. CVD diamond coated inserts are tested and compared to uncoated cemented carbide inserts and Polycrystalline diamond tipped inserts, in milling, turning and in refined tribological methods. The workpiece material in both the machine tests and the tribological tests is a high strength aluminum of the name Alumec 89. The machine tests were performed for 5 and 60 seconds at three cutting speeds, 600, 900 and 1200 m/min, keeping other parameters constant. The cutting inserts, the chips and the generated workpiece surface are examined using LOM, SEM and EDS. In the refined tribological testing, a pin-turning tribometer is used, with pins of uncoated and coated (CVD diamond) cemented carbide pins. These are tested at 5 and 30 seconds at 600 and 1200 m/min, applying a constant force of 10 N. In addition, a friction test was performed to measure the friction of the uncoated and the CVD diamond coated cemented carbide. Like the cutting inserts, the used pins were examined in LOM and SEM. The results show that while a large amount of built-up layer and built-up edges gather when using uncoated cemented carbide tools, only minimal amounts can be detected on CVD diamond and PCD. It has also been shown that the reason for the reduced adhesion in the case of diamond tooling materials is most likely due to the lack of chemical interactions between the diamond and the aluminum. The friction of the CVD diamond material was shown to be lower compared to the cemented carbide. The surface finish generated by the different materials, was the best in the case of PCD while the CVD generated multiple

The term thermal capacity appears to suggest a storable thermal quantity. However, this claim is not redeemed when thermal capacity is projected onto “heat”, which, like all energy forms, exits only in transit and is not a part of internal energy. The storable thermal quantity is entropy, and entropy capacity is a well-defined physical coefficient which has the advantage of being a susceptibility. The inverse of the entropy capacity relates the response of the system (change of temperature) to a stimulus (change of entropy) such as the fluid level responses to a change in amount of fluid contained in a vessel. Frequently, entropy capacity has been used implicitly, which is clarified in examples of the low-temperature analysis of phononic and electronic contributions to the thermal capacity of solids. Generally, entropy capacity is used in the estimation of the entropy of a solid. Implicitly, the thermoelectric figure of merit refers to entropy capacity. The advantage of the explicit use of entropy capacity comes with a descriptive fundamental understanding of the thermal behaviour of solids, which is made clear by the examples of the Debye model of phonons in solids, the latest thermochemical modelling of carbon allotropes (diamond and graphite) and not least caloric materials. An electrocaloric cycle of barium titanate close to its paraelectric–ferroelectric phase transition is analysed by means of entropy capacity. Entropy capacity is a key to intuitively understanding thermal processes.

We describe a vision for a national-scale heavy mineral (HM) map generated through automated mineralogical identification and quantification of HMs contained in floodplain sediments from large catchments covering most of Australia. The composition of the sediments reflects the dominant rock types in each catchment, with the generally resistant HMs largely preserving the mineralogical fingerprint of their host protoliths through the weathering-transport-deposition cycle. Heavy mineral presence/absence, absolute and relative abundance, and co-occurrence are metrics useful to map, discover and interpret catchment lithotype(s), geodynamic setting, magmatism, metamorphic grade, alteration and/or mineralization. Underpinning this vision is a pilot project, focusing on a subset from the national sediment sample archive, which is used to demonstrate the feasibility of the larger, national-scale project. We preview a bespoke, cloud-based mineral network analysis (MNA) tool to visualize, explore and discover relationships between HMs as well as between them and geological settings or mineral deposits. We envisage that the Heavy Mineral Map of Australia and MNA tool will contribute significantly to mineral prospectivity analysis and modeling, particularly for technology critical elements and their host minerals, which are central to the global economy transitioning to a more sustainable, lower carbon energy model.

Reducing the thickness of a material to its two-dimensional (2D) limit can have dramatic consequences for its collective electronic states, including magnetism, superconductivity, and charge and spin ordering. An extreme case is TiTe2, where a charge density wave (CDW) emerges in the single-layer, which is absent for the bulk compound, and whose origin is still poorly understood. Here, we investigate the electronic band structure evolution across this CDW transition using temperature-dependent angle-resolved photoemission spectroscopy. Our study reveals an orbital-selective band hybridisation between the backfolded conduction and valence bands occurring at the CDW phase transition, which in turn leads to a significant electronic energy gain, underpinning the CDW transition. For the bulk compound, we show how this energy gain is almost completely suppressed due to the three-dimensionality of the electronic band structure, including via a k(z)-dependent band inversion which switches the orbital character of the valence states. Our study thus sheds new light on how control of the electronic dimensionality can be used to trigger the emergence of new collective states in 2D materials.