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Network-based biocomputation (NBC) relies on accurate guiding of biological agents through nanofabricated channels produced by lithographic patterning techniques. Here, we report on the large-scale, wafer-level fabrication of optimized microfluidic channel networks (NBC networks) using electron-beam lithography as the central method. To confirm the functionality of these NBC networks, we solve an instance of a classical non-deterministic-polynomial-time complete (“NP-complete”) problem, the subset-sum problem. The propagation of cytoskeletal filaments, e.g., molecular motor-propelled microtubules or actin filaments, relies on a combination of physical and chemical guiding along the channels of an NBC network. Therefore, the nanofabricated channels have to fulfill specific requirements with respect to the biochemical treatment as well as the geometrical confienement, with walls surrounding the floors where functional molecular motors attach. We show how the material stack used for the NBC network can be optimized so that the motor-proteins attach themselves in functional form only to the floor of the channels. Further optimizations in the nanolithographic fabrication processes greatly improve the smoothness of the channel walls and floors, while optimizations in motor-protein expression and purification improve the activity of the motor proteins, and therefore, the motility of the filaments. Together, these optimizations provide us with the opportunity to increase the reliability of our NBC devices. In the future, we expect that these nanolithographic fabrication technologies will enable production of large-scale NBC networks intended to solve substantially larger combinatorial problems that are currently outside the capabilities of conventional software-based solvers.

The synthesis of 1‐Fc‐ (3), 1‐Br‐6‐Fc‐ (5 a), 2‐Br‐7‐Fc‐ (7 a), 1,6‐Fc2‐ (5 b), 2,7‐Fc2‐pyrene (7 b), 3,6‐Fc2‐9,10‐phenanthrenedione (10), and 3,6‐Fc2‐9,10‐dimethoxyphenanthrene (12; Fc=Fe(η5‐C5H4)(η5‐C5H5)) is discussed. Of these compounds, 10 and 12 form 1D or 2D coordination polymers in the solid state. (Spectro)Electrochemical studies confirmed reversible Fc/Fc+ redox events between −130 and 160 mV. 1,6‐ and 2,7‐Substitution in 5 a (E°′=−130 mV) and 7 a (E°′=50 mV) influences the redox potentials, whereas the ones of 5 b and 7 b (E°′=20 mV) are independent. Compounds 5 b, 7 b, 10, and 12 show single Fc oxidation processes with redox splittings between 70 and 100 mV. UV/Vis/NIR spectroelectrochemistry confirmed a weak electron transfer between FeII/FeIII in mixed‐valent [5 b]+ and [12]+. DFT calculations showed that 5 b non‐covalently interacts with the single‐walled carbon nanotube (SWCNT) sidewalls as proven by, for example, disentangling experiments. In addition, CV studies of the as‐obtained dispersions confirmed exohedral attachment of 5 b at the SWCNTs., Ferrocene complexes: The synthesis of 1‐Fc‐, 1‐Br‐6‐Fc‐, 2‐Br‐7‐Fc‐, 1,6‐Fc2‐, 2,7‐Fc2‐pyrene, 3,6‐Fc2‐9,10‐phenanthrenedione, and 3,6‐Fc2‐9,10‐dimethoxyphenanthrene (Fc=Fe(η5‐C5H4)(η5‐C5H5)) is discussed. Two of these compounds form 1D or 2D coordination polymers in the solid state. (Spectro)electrochemical studies confirmed reversible Fc/Fc+ redox events between −130 and 160 mV.

The adsorption of chiral molecules was recently shown to trigger a change in the magnetisation of mesoscopic magnetic domains in a ferromagnetic underlayer. In this work, we investigated the macroscopic (magneto-)optical response of chemisorbed α-helical polyalanine self-assembled monolayers (SAMs) on a gold and gold-capped-cobalt thin film on Au substrates using spectroscopic ellipsometry and magneto-optical Kerr effect spectroscopy and microscopy. The optical and magneto-optical spectra reveal selective chemisorption of the α-helical polyalanine molecules depending on the orientation of the substrate remanent magnetisation during the SAMs process. Moreover, a sign change of the magneto-optical response was observed in some of the magnetic substrates after the chiral SAMs formation.

The ¦-ketoiminato complex [Pd(OAc)L] (3) can be synthesized by the reaction of bis(benzoylacetone)diethylenetriamine (1, = LH) with [Pd(OAc)2] (2). The structure of 3 in the solid state has been determined by single X-ray diffraction analysis. Complex 3 crystallizes as a dimer (3 2), which is formed by hydrogen bonds between NH and OOAc functionalities of two adjacent ligands. Each of the Pd atoms is complexed by one ON2 donor unit of the polydentate ligand L − and an acetate group. Pd–Pd interactions and hydrogen bond formation between a NH and the C=O acetate moiety lead to a [4 + 2] coordination at Pd. The non-coordinated part of L exists in its ¦-keto-enamine form. The thermal decomposition behavior of 3 2 was studied by TG (thermogravimetry) and TG-MS showing that 3 2 decomposes between 200 and 500°C independent of the applied atmosphere. Under oxygen PdO is produced, while under argon Pd is formed as confirmed by PXRD measurements. Complex 3 2 was applied as a spin-coating precursor (conc. 0.1 mol L−1, volume 1.5 mL, 3000 rpm, deposition time 6 min, heating rate 50 K min−1, holding time 60 min (Ar) and 120 min (air) at T = 800°C). The as-obtained samples are characterized by granulated particles of Pd/PdO on the substrate surface. EDX (energy-dispersive X-ray spectroscopy) and XPS (X-ray photoelectron spectroscopy) measurements confirmed the formation of Pd (Ar) or PdO (O2) with up to 12 mol% C impurity.

Macroscopic materials made of two-dimensional components such as flakes of graphene or transition metal dichalcogenides represent a material class with great potential for large-scale applications. Depending on the structure, they can inherit the exceptional properties of the nanoscale building blocks while developing new features on the macroscopic scale. Supported by theoretical considerations and finite element analysis, we developed a network simulation method to model 2D-based electrical conductors. Here, we systematically explain the technical and methodological details of our approach, using the example of graphene-based conductor materials. Apart from the raw material properties, we discuss the importance of homogeneity and internal structure of the material. Our findings are supported by finite element analysis. We demonstrate the application of our method by studying the intricate interaction of several material parameters and the resulting effect on the macroscopic network. Finally, we provide guidelines for adapting our method to different physical situations.

Complexes [Fe(β-diketonate)3] (β-diketonate = 2-acetylcyclopentanoate (3a), = 2-acetylcyclohexanoate (3b), = 4,4-dimethyl-1-phenyl pentanedionate (3c)) were synthesized by the reaction of FeCl3 with the respective β-diketones in presence of NaOH. The molecular structures of 3a and 3c in the solid state are discussed, confirming an octahedral coordination sphere at Fe(III) setup by the three bidentate-bonded β-diketonato ligands. Variation of the β-diketonato ligands allowed to influence the thermal behavior and vapor pressure of the complexes. TG-MS ( = Thermo Gravimetry-Mass Spectrometry) studies, exemplarily carried out on 3a, confirmed the release of the β-diketonate ligands. Complexes 3a–c were applied as MOCVD (=Metal-Organic Chemical Vapor Deposition) precursors for the deposition of Fe2O3 thin films on silicon substrates. It was found that with 3a,b, conformal and dense carbon-free γ- and α-Fe2O3 layers were produced at 450 °C, which was verified by scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray photon spectroscopy.

The interaction of thin evaporating fluid films with solids is studied using the example of water on LiTaO3 (LTO). Adsorption energies are computed by ab initio density functional theory (DFT) and used to calculate the Gibbs free energy of adsorption of water on LTO. Integrating the disjoining pressure, consisting of molecular and structural components, with respect to film thickness gives an expression for the Gibbs free energy. In this way, parameters for the disjoining pressure can be calculated by fitting its integral to the Gibbs free energy computed by ab initio DFT. A combination of literature-known models for spin drying and evaporation is utilized to describe the temporal evolution of the water layer. The vapor above the water layer is modeled by diffusion and a mass balance is applied at the water–air interface. For thick initial layers, an analytical approximation is derived which only depends on fluid and ambient conditions but not on the substrate properties.

We present a combined experimental and theoretical study of the two-dimensional electron states at the iridium-silicide surface of the antiferromagnet GdIr2Si2 above and below the Neel temperature. Using angle-resolved photoemission spectroscopy (ARPES) we find a significant spin-orbit splitting of the surface states in the paramagnetic phase. By means of ab initio density-functional-theory (DFT) calculations we establish that the surface electron states that reside in the projected band gap around the M¯ point exhibit very different spin structures which are governed by the conventional and the cubic Rashba effect. The latter is reflected in a triple spin winding, i.e., the surface electron spin reveals three complete rotations upon moving once around the constant energy contours. Below the Neel temperature, our ARPES measurements show an intricate photoemission intensity picture characteristic of a complex magnetic domain structure. The orientation of the domains, however, can be clarified from a comparative analysis of the ARPES data and their DFT modeling. To characterize a single magnetic domain picture, we resort to the calculations and scrutinize the interplay of the Rashba spin-orbit coupling field with the in-plane exchange field, provided by the ferromagnetically ordered 4f moments of the near-surface Gd layer. (Less)

Discovered in 1962, the divalent ferromagnetic semiconductor EuS (TC = 16.5 K, Eg = 1.65 eV) has remained constantly relevant to the engineering of novel magnetically active interfaces, heterostructures, and multilayer sequences and to combination with topological materials. Because detailed information on the electronic structure of EuS and, in particular, its evolution across TC is not well-represented in the literature but is essential for the development of new functional systems, the present work aims at filling this gap. Our angle-resolved photoemission measurements complemented with first-principles calculations demonstrate how the electronic structure of EuS evolves across a paramagnetic–ferromagnetic transition. Our results emphasize the importance of the strong Eu 4f–S 3p mixing for exchange-magnetic splittings of the sulfur-derived bands as well as coupling between f and d orbitals of neighboring Eu atoms to derive the value of TC accurately. The 4f–3p mixing facilitates the coupling between 4f and 5d orbitals of neighboring Eu atoms, which mainly governs the exchange interaction in EuS., This work was supported by the German Research Foundation (DFG) through Grant No. KR3831/5-1, No. LA655/20-1, No. SFB1143 (Project No. 247310070), and No. TRR288 (422213477, project A03). We acknowledge support from the Russian Foundation for Basic Research (Grant No. 20-32-70127) and Saint-Petersburg State University (Grant No. ID 73028629). S.V.E. acknowledges support from a government research assignment for ISPMS SB RAS (Project FWRW-2019-0032). We acknowledge MAX-IV Laboratory for time on the Bloch Beamline under Proposal 20190824. Research conducted at MAX IV, a Swedish national user facility, is supported by the Swedish Research council under contract 2018-07152, the Swedish Governmental Agency for Innovation Systems under contract 2018-04969, and Formas under contract 2019-02496. The research has also been supported by the project CALIPSO plus under Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020.

We present and discuss the methodology for modeling $4f$ photoemission spectra, $4f$ photoelectron diffraction (PED) patterns, and magnetic dichroism effects for rare-earth-based materials. Using PED and magnetic dichroism in photoemission, we explore the electronic and magnetic properties of the near-surface region of the valence-fluctuating material ${\mathrm{EuIr}}_{2}{\mathrm{Si}}_{2}$. For the Eu-terminated surface, we found that the topmost Eu layer is divalent and exhibits a ferromagnetic order below 10 K. The valency of the next Eu layer, that is the fifth atomic layer, is about 2.8 at low temperature that is close to the valency in the bulk. The properties of the Si-terminated surface are drastically different. The first subsurface Eu layer (fourth atomic layer below the surface) behaves divalently and orders ferromagnetically below 48 K. Experimental data indicate, however, that there is an admixture of trivalent Eu in this layer, resulting in its valency of about 2.1. The next deeper lying Eu layer (eighth atomic layer below the surface) behaves mixed valently, but the estimated valency of 2.4 is notably lower than the value in the bulk. The presented approach and obtained results create a background for further studies of exotic surface properties of $4f$-based materials, and allow us to derive information related to valency and magnetism of individual rare-earth layers in a rather extended area near the surface.

The network- and pore-properties in porous CVD and spin-on organosilicate glasses (OSG) were investigated by Fourier transform infrared (FTIR) and positron annihilation lifetime spectroscopy (PALS). Thermal treatments were carried out from room temperature up to 450 °C to observe the porogen degradation by forming a porous network. For spin-on dielectrics a complete porogen removal was achieved at 450 °C creating a mean pore diameter of 3.1 nm, whereas a onset of pore inter-connectivity was precisely estimated at around 400 °C.

Nanoscale, low-phase-noise, tunable transmitter-receiver links are key for enabling the progress of wireless communication. We demonstrate that vortex-based spin-torque nano-oscillators, which are intrinsically low-noise devices because of their topologically protected magnetic structure, can achieve frequency tunability when submitted to local ion implantation. In the experiments presented here, the gyrotropic mode is excited with spin-polarized alternating currents and anisotropic magnetoresistance measurements yield discrete frequencies from a single device. Indeed, chromium-implanted regions of permalloy disks exhibit different saturation magnetization than neighboring, non-irradiated areas, and thus different resonance frequency, corresponding to the specific area where the core is gyrating. Our study proves that such devices can be fabricated without the need for further lithographical steps, suggesting ion irradiation can be a viable and cost-effective fabrication method for densely packed networks of oscillators.

Carbon nanotube (CNT)-based field-effect transistors have demonstrated great potential for high-frequency (HF) analog transceiver electronics. Despite significant advancements, one of the remaining challenges is the optimization of the device architecture for obtaining the highest possible speed and linearity. While most studies so far have concentrated on symmetrical top gated FET devices, we report on the impact of the device architecture on their HF performance. Based on a wafer-level nanotechnology platform and device simulations, transistors with a buried gate having different widths and positions in the FET channel have been fabricated. Analysis of several FETs with nonsymmetrical gate electrode location in the channel revealed a speed increase of up to 18% measured by the external transit frequency fT and maximum frequency of oscillation fmax. Although only randomly oriented CNTs with a density of 25 CNTs/μm and 280 nm long channels were used in this study, transit frequencies up to 14 GHz were obtained.

The performance of CoFeB/MgO tunnel junctions is strongly dependent on an annealing step at the end of the fabrication process to first, set a reference magnetization through the exchange bias effect and second, to crystallize the MgO/CoFe layers while boron diffuses out, in order to maximize the magnetoresistance ratio. In this regard, a laser-induced annealing process presents several advantages against traditional oven annealing techniques, providing a scalable approach with no limitations regarding the defined reference magnetization that can be aligned in different directions on a wafer. This paper concentrates on the mechanisms and dependences of laser annealing on the magnetic properties in comparison to the standard vacuum oven annealing, providing a first insight for the applicability of laser annealing for CoFeB-/MgO-based magnetic tunnel junctions with all concomitant needs.

We have investigated ferroelectric charged domains in polycrystalline hexagonal yttrium manganite thin films (Y1Mn1O3, Y0.95Mn1.05O3, Y1Mn0.99Ti0.01O3, and Y0.94Mn1.05Ti0.01O3) by scanning electron microscopy (SEM) in secondary electron emission mode with a small acceleration voltage. Using SEM at an acceleration voltage of 1.0 kV otherwise homogenous surface charging effects are reduced, polarization charges can be observed and polarization directions (±Pz) of the ferroelectric domains in the polycrystalline thin films can be identified. Thin films of different chemical composition have been deposited by pulsed laser deposition on Pt/SiO2/Si structures under otherwise same growth conditions. Using SEM it has been shown that different charged domain density networks are existing in polycrystalline yttrium manganite thin films.

Spin-orbit interaction and structure inversion asymmetry in combination with magnetic ordering is a promising route to novel materials with highly mobile spin-polarized carriers at the surface. Spin-resolved measurements of the photoemission current from the Si-terminated surface of the antiferromagnet TbRh2Si2 and their analysis within an ab initio one-step theory unveil an unusual triple winding of the electron spin along the fourfold-symmetric constant energy contours of the surface states. A two-band k⋅p model is presented that yields the triple winding as a cubic Rashba effect. The curious in-plane spin-momentum locking is remarkably robust and remains intact across a paramagnetic-antiferromagnetic transition in spite of spin-orbit interaction on Rh atoms being considerably weaker than the out-of-plane exchange field due to the Tb 4f moments., This work was supported by the German Research Foundation (Grants No. KR-3831/5-1, No. LA655/20-1, GRK1621, Fermi-NESt No. ANR-16-CE92-0018, and SFB1143, project-id 247310070) and the Spanish Ministry of Science, Innovation, and Universities (Grant Nos. FIS2016-76617-P and MAT-2017-88374-P). We also acknowledge funding from the Department of Education of the Basque government (Grant No. IT1164-19), St. Petersburg State University (Project ID 51126254), and the Russian Foundation for Basic Research (Grant No. 20-32-70127). The SR-ARPES experiments at HiSOR were performed with the approval of the Proposal Assessing Committee of the Hiroshima Synchrotron Radiation Center (Proposal No. 18BG023). We also acknowledge the Impuls-und Vernetzungsfonds der Helmholtz Gemeinschaft (Grant No. HRSF-0067)

CoFeB alloys are highly relevant materials for spintronic applications. In this work, the crystallization of CoFeB alloys triggered by thermal annealing was investigated by x-ray diffraction techniques and scanning electron microscopy, as well as spectroscopic ellipsometry and magneto-optical Kerr effect spectroscopy for annealing temperatures ranging from 300 to ${600}^{\ensuremath{\circ}}\mathrm{C}$. The transformation of \ensuremath{\sim}100-nm-thick ${\mathrm{Co}}_{x}{\mathrm{Fe}}_{(80\ensuremath{-}x)}{\mathrm{B}}_{20}$ films from amorphous to polycrystalline was revealed by the sharpening of spectral features observed in optical and magneto-optical dielectric functions spectra. The influence of B on the dielectric function was assessed both experimentally and by optical modeling. By analyzing the Drude component of the optical dielectric function, a consistent trend between the charge-carrier scattering time/resistivity and the annealing temperature was observed, in agreement with the electrical investigations by means of the four-point-probe method.

Graphene-based conductors such as films and fibers aim to transfer graphene's extraordinary properties to the macroscopic scale. They show great potential for large-scale applications, but there is a lack of theoretical models to describe their electrical characteristics. We present a network simulation method to model the electrical conductivity of graphene-based conductors. The method considers all of the relevant microscopic parameters such as graphene flake conductivity, interlayer conductivity, packing density, and flake size. To provide a mathematical framework, we derive an analytical expression, which reproduces the essential features of the network model. We also find good agreement with experimental data. Our results offer production guidelines and enable the systematic optimization of high-performance graphene-based conductor materials. A generalization of the model to any conductor based on two-dimensional materials is straightforward.

Lanthanide clusters [Ln4(μ3-OH)2(η2-accp)4((μ-O)-η2-accp)6] (Ln = Y (4), Gd (5); accp = 2-acetylcyclopentanoate) are accessible by treatment of [M(NO3)3·6H2O] (M = Y (1), Gd (2)) with 3 equiv. of Haccp (3) in presence of NaOH. The molecular structures of 4 and 5 in the solid-state are discussed. The thermal behavior of 4 and 5 was studied by TG under Ar and O2, showing multistep decomposition processes. Additionally, DSC studies were carried out under an atmosphere of O2. PXRD measurements of the TG residues confirm the formation of Ln2O3. Spin-coating experiments were carried out with 4 and 5 for Ln2O3 film deposition on silicon substrates. The layers are smooth, close and are of thicknesses of 18.87 ± 1.13 nm and 25.59 ± 4.55 nm for Ln = Y and Gd, which was evidenced by SEM and EDX studies. Field-effect transistors were successfully fabricated by deposition of carbon nanotubes on top of the Y2O3 films and formation of palladium contacts by a lift-off procedure. An on/off ratio of more than 4 orders of magnitude is achieved without considerable leakage currents. These results demonstrate the potential use of spin-coated Y2O3 as a gate dielectric in electronic devices.

Wafer-level catalytic chemical vapour deposition (CCVD) of semiconducting enriched single-walled carbon nanotubes (sc-SWCNTs) with high quality is of high interest for industrial realization of SWCNT-based sensor and electronic applications. While bimetallic catalysts systems are known to favor type-enriched growth of SWCNTs, surface morphological evolution of different bimetallic catalyst stacks during catalyst conditioning as well as its impact on SWCNTs growth is not clearly understood. Here, we present a systematic study on the effect of bimetallic catalyst composition, layer stack thickness configuration as well as CCVD process parameters on the composition of grown SWCNTs. Besides the well-known Co and Co-Mo system, the Co-Ru system was investigated. We found that in case of Co-Mo bimetallic system, highest degree of sc-SWCNTs content is achieved using bilayer configuration Co-Mo:0.2–0.1 nm processed at 810 °C and 20 kPa total pressure. In case of Co-Ru bimetallic system, highest degree of sc-SWCNTs content is achieved using Co-Ru:0.1–0.1 nm processed at 840 °C and 10 kPa total pressure.

Next to powders, inks, and microelectronics, many technologies that carry the attribute nano in their name are still waiting for their breakthrough and wide acceptance in engineering and industry. At least nanofabrication technologies are the subject of a vivid track in research and development in a variety of scientific fields but yet most of them are mainly invisible in everyday products. This paper aims to describe three inspiring examples of research work in the area of nanopatterning and systems integration at the micro-nano interface to motivate applications with new and unprecedented functionalities. The application examples comprise the fields of bio-inspired computing, optoelectronic sensing, and spectral imaging. First, network-based biocomputing uses biological agents in a nanopatterned fluidic channel system and opens horizons for energy-efficient solutions to complex mathematical problems. Second, nanoelectronic devices based on carbon nanotubes (CNTs) have emerged because of the outstanding mechanical, electronic, and optical properties of the CNTs. The adaptivity of nanostructures to the world of biological molecules and other nanoscopic building blocks such as quantum dots and nanoparticles enables novel, even personalized, devices and technical solutions. Third, early-on ""nano"" fame has been devoted to optical effects-the authors here discuss an advanced integrated micro-opto-mechanical system on a micromirror plate forming a Fabry-Pérot Interferometer.

The synthesis of ketoiminato copper(ii) complexes [Cu(OCRCHC(CH3)NCH2CH2X)(μ-OAc)]2 (X = NMe2: 4a, R = Me; 4b, R = Ph. X = OMe: 5, R = Me) and [Cu(OCRCHCMeNCH2CH2NEt2)(OAc)] (6, R = Me) from RC(O)CHC(CH3)N(H)CH2CH2X (X = NMe2: 1a, R = Me; 1b, R = Ph. X = NEt2: 1c, R = Me. X = OMe: 2, R = Me) and [Cu(OAc)2·H2O] (3) is reported. The molecular solid-state structures of 4-6 were determined by single crystal X-ray diffraction studies, showing that 4a,b and 5 are dimers which are set up by two [{Cu(μ-OAc)L}] (L = ketoiminato ligand) units featuring a square-planar Cu2O2 core with a distorted square-pyramidal geometry at Cu(ii). In contrast, 6 is monomeric with a tridentate-coordinated OCMeCHCMeNCH2CH2NEt2 ligand and a σ-bonded acetate group, thus inducing a square-planar environment around Cu(ii). The thermal behavior of all complexes was studied by TG (Thermogravimetry) and DSC (Differential Scanning Calorimetry) under an atmosphere of Ar and O2. Complex 4b shows the highest first onset temperature at 213 °C (under O2) and 239 °C (Ar). PXRD studies confirmed the formation of CuO under an atmosphere of O2 and Cu/Cu2O under Ar. TG-MS studies, exemplarily carried out with 4a, indicate the elimination of the ketoiminato ligands with detectable fragments such as m/z = 15, 28, 43, 44, 45, and 60 at a temperature above 250 °C. Vapor pressure measurements displayed that 5 shows the highest volatility of 3.6 mbar at 70 °C (for comparison, 4a, 1.4; 4b, 1.3; 6, 0.4 mbar) and hence 4a and 5 were used as MOCVD precursors for Cu/Cu2O deposition on Si/SiO2 at substrate temperatures of 450 °C and 510 °C. The deposition experiments were carried out under an atmosphere of nitrogen as well as oxygen. The as-obtained layers were characterized by SEM, EDX, XPS, and PXRD, showing that with oxygen as the reactive gas a mixture of metallic copper and copper(i) oxide without carbon impurities was formed, while under N2 Cu films with 53-68 mol% C contamination were produced. In a deposition experiment using precursor 5 at 510 °C under N2 a pure copper film was obtained.

In this study, we aim to develop a ReaxFF reactive force field for simulating the reaction mechanism of copper atomic layer deposition (ALD). To achieve this, we optimized the Cu/C, Cu/H, and Cu/N parameters of ReaxFF and extended the existing Cu potential to describe Cu/C/H/O/N interactions involved in Cu ALD. The parametrization procedure was implemented through an efficient multiparameter and parallel optimization scheme based on the Taguchi method. Using the newly developed Cu potential, we performed reactive molecular dynamics (RMD) simulations on an “abbreviated” ALD cycle using a [Cu(iPr-amd)]2 (iPr-amd = N,N′-diisopropylacetamidinate) or Cu(dmap)2 (dmap = dimethylamino-2-propoxide) precursor with the H radical as a coreactant. In the first half-cycle, the [Cu(iPr-amd)]2 precursor is found to adsorb dissociatively on the Cu surface as Cu(iPr-amd) monomers. During the second half-cycle, H radicals partly eliminate precursor fragments to the gas phase, but some intermediates such as C5H12N2 and C2H4N...

The inelastic scattering of fast neutrons from 7Li nuclei was investigated at the nELBE neutron-time-of-flight facility. The photon production cross section of 478 keV γ-rays from the first excited state of 7Li was determined by irradiating a disc of LiF with neutrons of energies ranging from 100 keV to about 10 MeV. The target position was surounded by a setup of 7 LaBr3 scintillation detectors and 7 high-purity germanium detectors to detect the de-excitation γ-rays. A 235U fission chamber was used to determine the incoming neutron flux. The number of detected photons was corrected for the detection efficiency, multiple scattering and the time-of-flight dependent data acquisition dead time. The preliminary results show reasonable agreement with some previous measurments but are about 15 % below the recent data taken at the GELINA facility.

The wafer-level integration of high aspect ratio silicon nanostructures is an essential part of the fabrication of nanodevices. Metal-assisted chemical etching (MACE) is a promising low-cost and high-volume technique for the generation of vertically aligned silicon nanowires. Noble metal nanoparticles were used to locally etch the silicon substrate. This work demonstrates a bottom-up self-assembly approach for noble metal nanoparticle formation and the subsequent silicon wet etching. The macroscopic wafer patterning has been done by using a poly(methyl methacrylate) masking layer. Different metals (Au, Pt, Pd, Cu, and Ir) were investigated to derive a set of technologies as platform for specific applications. Especially, the shape of the 3D structures and the resulting reflectance have been investigated. The Si nanostructures fabricated using Au nanoparticles show a perfect light absorption with a reflectance below 0.3%. The demonstrated technology can be integrated into common fabrication processes for microelectromechanical systems.

The emergence of ferromagnetism in Rashba systems, where the evolving exchange interaction enters into competition with spin-orbit coupling, leads to a nontrivial spin-polarized electronic landscape with an intricate momentum-dependent spin structure, which is challenging to unveil. Here, we show a way to disentangle the contributions from the effective spin-orbit and exchange fields and thus to gain knowledge of the spin structure in ferromagnetic Rashba materials, which is required for spintronic applications. Our approach is based exclusively on spin-integrated photoemission measurements combined with a two-band modeling. As an example, we consider the mixed-valent material EuIr2Si2 which, while being nonmagnetic in the bulk, reveals strong ferromagnetism at the iridium-silicide surface where both spin-orbit and exchange magnetic interactions coexist. The combined effect of these interactions causes a complex band dispersion of the surface state which can be observed in photoemission experiments. Our method allows us to comprehensively unravel the surface-state spin structure driven by spin-orbit coupling at the ferromagnetic surface. This approach opens up opportunities to characterize the spin structure of ferromagnetic Rashba materials, especially where dedicated spin-resolved measurements remain challenging., This work was supported by Saint Petersburg State University (Grant No. ID 51126254) and the Russian Foundation for Basic Research (Grant No. 20-32-70127). We acknowledge financial support from the Spanish Ministry of Economy (No. MAT-2017-88374-P) and the German Research Foundation (DFG) through Grants No. LA655/20-1, No. KR3831/5-1, and Fermi-NEst. We acknowledge Diamond Light Source for access to beamline I05 (Proposals No. SI18844-1 and No. SI17761-1).

The synthesis and solid‐state structure of Ru(CO)2(PEt3)2(O2CR)2 (4a–f, R = Me, Et, iPr, tBu, CH2OMe, CF3) is reported. The vapor pressure of 4a–f was measured, ranging from 6.3 mbar (4f) to 14.8 at 190 °C (4e). Complexes 4a–f decompose between 210–350 °C of which 4c shows the lowest (248 °C) and 4e (280 °C) the highest onset temperature. TG‐MS studies (4f) showed subsequent decarbonylation and decarboxylation processes. To determine the gas phase composition VT IR studies were performed. Based on TG‐MS, VT IR and DFT calculations decomposition mechanisms are discussed. Complexes 4a–f are suited as MOCVD precursors, producing dense layers of 25–50 nm thickness, consisting of 57 at‐% Ru, up to 18.2 at‐% P and as impurities C, N and O. A carbon‐free Ru(P) layer was obtained with 4a as CVD precursor.