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The research aimed to study the effectiveness of a proposed course in nanophysics and its technological applications to develop nanotechnology concepts and attitudes towards them among second-year secondary school students. To conduct this research, the experimental method was used with a quasi-experimental design based on a single-group design with pre- and post- tests. The research sample consisted of (45) second-year secondary school students. The proposed unit was taught in the first semester of the academic year 2023-2024 AD, and the research tools were applied to them, which are a test to measure nanotechnology concepts and a scale of attitudes towards them. After completing teaching for the research group, applying the research tools before and after, and processing the results statistically, the results showed that the students of the research group outperformed the post-application over the pre- application with a statistically significant difference at a significance level of (0.01) in terms of developing nanotechnology concepts and attitudes towards them, as the research results indicated the effectiveness of the proposed unit in developing the research variables. The research recommended integrating the proposed unit into the physics curriculum for second-year secondary school students. [ABSTRACT FROM AUTHOR]

Since 2012, the National Nanoscience Teaching and Training Platform (NNPTTP), funded by the South African Department of Science and Innovation (DSI), has been responsible for overseeing Africa's first-ever master's in nanoscience program. For over a decade, the NNPTTP has seen the cooperation of four partner universities across South Africa, namely, the University of Johannesburg (UJ), University of the Free State (UFS), University of the Western Cape (UWC), and Nelson Mandela University (NMU), culminating in over 250 graduates trained in either nanophysics, nanochemistry, or nanobiology. Originally established to train professionals for a nanotechnology-based industry, both in South Africa and internationally, the program and platform has evolved into a testament to scientific collaboration. This paper discusses the program's framework, successes and challenges, related research, and future plans. [ABSTRACT FROM AUTHOR]

Since 2012, the National Nanoscience Teaching and Training Platform (NNPTTP), funded by the South African Department of Science and Innovation (DSI), has been responsible for overseeing Africa’s first-ever master’s in nanoscience program. For over a decade, the NNPTTP has seen the cooperation of four partner universities across South Africa, namely, the University of Johannesburg (UJ), University of the Free State (UFS), University of the Western Cape (UWC), and Nelson Mandela University (NMU), culminating in over 250 graduates trained in either nanophysics, nanochemistry, or nanobiology. Originally established to train professionals for a nanotechnology-based industry, both in South Africa and internationally, the program and platform has evolved into a testament to scientific collaboration. This paper discusses the program’s framework, successes and challenges, related research, and future plans.

Nanophysics is rapidly developing for the recent couple of decades. Unique physical properties of materials at the nanoscale are the reason for this rapid development. Ideas, materials and structures of nanophysics have found their wide application in related fields of modern science, including biology and medicine. This short review is devoted to the application of nanophysics in modern medicine. The main focus was on application of ideas and physical phenomena of nanophysics in oncology and antiviral therapy. We have focused on the use of nanosystems both for tumor imaging and for the struggle against some types of tumors. The use of nanoparticles as nanocontainers for targeted drug delivery was briefly discussed. We also demonstrated how the effects of nanophysics can be used to develop new non-traditional methods of antiviral therapy. The focus of these methods was the idea of physical (field) action of nanoparticles on the viruses, which is based on the local-field enhancement effect that is the reason of ponderomotive forces acting on the viruses up to destruction of viral envelopes. [ABSTRACT FROM AUTHOR]

Credibility building activities in computational research include verification and validation, reproducibility and replication, and uncertainty quantification. Though orthogonal to each other, they are related. This paper presents validation and replication studies in electromagnetic excitations on nanoscale structures, where the quantity of interest is the wavelength at which resonance peaks occur. The study uses the open-source software PyGBe: a boundary element solver with treecode acceleration and GPU capability. We replicate a result by Rockstuhl et al. (2005, doi:10/dsxw9d) with a two-dimensional boundary element method on silicon carbide (SiC) particles, despite differences in our method. The second replication case from Ellis et al. (2016, doi:10/f83zcb) looks at aspect ratio effects on high-order modes of localized surface phonon-polariton nanostructures. The results partially replicate: the wavenumber position of some modes match, but for other modes they differ. With virtually no information about the original simulations, explaining the discrepancies is not possible. A comparison with experiments that measured polarized reflectance of SiC nano pillars provides a validation case. The wavenumber of the dominant mode and two more do match, but differences remain in other minor modes. Results in this paper were produced with strict reproducibility practices, and we share reproducibility packages for all, including input files, execution scripts, secondary data, post-processing code and plotting scripts, and the figures (deposited in Zenodo). In view of the many challenges faced, we propose that reproducible practices make replication and validation more feasible. This article is part of the theme issue 'Reliability and reproducibility in computational science: implementing verification, validation and uncertainty quantification in silico'. [ABSTRACT FROM AUTHOR]

Theoretical calculations of the refractive index, optical dielectric constant and reflection coefficient for the Tl3XY4 crystal within Harrison's bonding orbital model were carried out. The detailed analysis of our calculations has been done to present deeper understanding of this investigation. The calculations were performed for the spectral region far from the absorption edge, where the dispersion of the refractive index is absent. The refractive index was determined within the generalized single-oscillator model. This approach allows determining the energies of occupied electronic states using the Hartree-Fock values for the valence levels in solids. We have used the simplification by including only nearest-neighbor couplings (clusters) and using universal parameters, which allows direct prediction of crystal physical properties. This cluster approximation based on a special point is used for calculations of bond polarizabilities. The real part of the dielectric function is determined from the imaginary part by the Kramers-Kronig relationship. Finally, we have used the Moss, Ravindra, Herve and Vandamme models for comparing the value of the refractive index calculated according the Harrison's model. The satisfactory agreement of our theoretical calculations is obtained. It was shown that Harrison's model allows analyzing the optical parameters of Tl3XY4 type compounds. The refractive index evaluation is of considerable importance for applications in integrated optic devices, where refractive index of materials is the key parameter for device design. The theoretical technique developed in this paper could be used for the investigation of the optical properties of materials. It should be noted that the crystal under investigation is expected to contribute to the development of nanophysics and personalized medicine for health monitoring and prevention. [ABSTRACT FROM AUTHOR]

Mesoscopic physics has become a mature field [...]

Electrons have played a significant role in the development of many fields of physics during the last century. The interest surrounding them mostly involved their wave-like features prescribed by the quantum theory. In particular, these features correctly predict the behaviour of electrons in various physical systems including atoms, molecules, solid-state materials, and even in free space. Ten years ago, new breakthroughs were made, arising from the new ability to bestow orbital angular momentum (OAM) to the wave function of electrons. This quantity, in conjunction with the electron’s charge, results in an additional magnetic property. Owing to these features, OAM-carrying, or twisted, electrons can effectively interact with magnetic fields in unprecedented ways and have motivated materials scientists to find new methods for generating twisted electrons and measuring their OAM content. Here, we provide an overview of such techniques along with an introduction to the exciting dynamics of twisted electrons. [ABSTRACT FROM AUTHOR]

We propose a general method for eliminating the reflection of waves in 2 dimensional photonic crystal waveguides (2D-PCWs), a kind of 2D material, by introducing extra scatterers inside the 2D-PCWs. The intrinsic reflection in 2D-PCWs is compensated by the backward-scattered waves from these scatterers, so that the overall reflection is greatly reduced and the insertion loss is improved accordingly. We first present the basic theory for the compensation method. Then, as a demonstration, we give four examples of extremely-low-reflection and high-transmission 90°bent 2D-PCWs created according to the method proposed. In the four examples, it is demonstrated by plane-wave expansion method and finite-difference time-domain method that the 90°bent 2D-PCWs can have high transmission ratio greater than 90% in a wide range of operating frequency, and the highest transmission ratio can be greater than 99.95% with a return loss higher than 43 dB, better than that in other typical 90°bent 2D-PCWs. With our method, the bent 2D-PCWs can be optimized to obtain high transmission ratio at different operating wavelengths. As a further application of this method, a waveguide-based optical bridge for light crossing is presented, showing an optimum return loss of 46.85 dB, transmission ratio of 99.95%, and isolation rates greater than 41.77 dB. The method proposed provides also a useful way for improving conventional waveguides made of cables, fibers, or metal walls in the optical, infrared, terahertz, and microwave bands. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A singular event related with the fall of a considerable amount of dust with anomalous characteristics is reported here, as well as the physicochemical characteristics of samples collected at the site in Lisbon-Portugal. The dust fall occurred during a rainy autumnal overnight and the geographic delimitation of the affected area, as well as the physical state in situ of the powder samples, are not compatible with the one that would be expected considering the climatic conditions registered at that time. The collected samples have been investigated, particularly by modern techniques involving nanoparticle analysis. The results prove that the samples have a very heterogeneous and granulated composition whose nanoparticle size distribution is bimodal (centered, respectively, about 90 and 120 nm) and containing some nanowhiskers and nanorods. Taking into account the official meteo data, it is likely that dust must have been transported by air and dried in the place (after rain) by unusual extremely localized-heat wave. However, the back trajectories software simulations point to a geographic source of clouds which soil chemical composition has no correlation with the chemical composition of the sample and where no industrial-relevant source is assigned. [ABSTRACT FROM AUTHOR]

The analogs of two seminal quantum optics experiments are considered in a condensed-matter setting with single-electron sources injecting electronic wave packets on edge states coupled through a quantum point contact. When only one electron is injected, the measurement of noise correlations at the output of the quantum point contact corresponds to the Hanbury-Brown and Twiss setup. When two electrons are injected on opposite edges, the equivalent of the Hong-Ou-Mandel collision is achieved, exhibiting a dip, as in the coincidence measurements of quantum optics. The Landauer-Büttiker scattering theory is used to first review these phenomena in the integer quantum Hall effect, next, to focus on two more exotic systems: edge states of two-dimensional topological insulators, where new physics emerges from time reversal symmetry and three-electron collisions can be achieved; and edges states of a hybrid Hall/superconducting device, which allow electron quantum optics experiments with Bogoliubov quasiparticles to be performed. [ABSTRACT FROM AUTHOR]

We report on a reversible structural phase transition of a two-dimensional system that can be locally induced by an external electric field. Two different structural configurations may coexist within a CO monolayer on Cu(111). The balance between the two phases can be shifted by an external electric field, causing the domain boundaries to move, increasing the area of the favored phase controllable both in location and size. If the field is further enhanced new domains nucleate. The arrangement of the CO molecules on the Cu surface is observed in real time and real space with atomic resolution while the electric field driving the phase transition is easily varied over a broad range. Together with the well-known molecular manipulation of CO adlayers, our findings open exciting prospects for combining spontaneous long-range order with man-made CO structures such as "molecule cascades" or "molecular graphene". Our new manipulation mode permits us to bridge the gap between fundamental concepts and the fabrication of arbitrary atomic patterns in large scale, by providing unprecedented insight into the physics of structural phase transitions on the atomic scale. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on Symanzik's approach, we propose a model of the interaction of a spinor with a material plane. We investigate the scattering of Dirac particles on the plane and the properties of states localized in its vicinity. The model can find application to a wide class of phenomena occurring during the interaction of quantum-electrodynamics fields with two-dimensional materials. [ABSTRACT FROM AUTHOR]

Classical and quantum Hall effects, measurement of electrochemical potentials, the Landauer formulas and Buttiker formula, measurement of Hall potential, an account of magnetic field in the NEGF method, quantum Hall effect, Landau method, and edge states in graphene are discussed in the frame of the «bottom- up» approach of modern nanoelectronics. [ABSTRACT FROM AUTHOR]

Basic topics of spintronics such as spin valve, interface resistance due to the mismatch of conduction modes, spin potentials, non-local spin voltage, spin moment and its transport, Landau-Lifshitz-Gilbert equation, and explanation on its basis why a magnet has an "easy axis", nanomagnet dynamics by spin current, polarizers and analyzers of spin current, diffusion equation for ballistic transport and current in terms of non-equilibrium potentials are discussed in the frame of the "bottom-up" approach of modern nanoelectronics. [ABSTRACT FROM AUTHOR]

It was identified the essential dependence of the potential surface shape of the H2O2 molecule and the barrier height during rotation of the molecule fragments around the O-O-bond on the external electric field. Its form allows to consider the hydrogen peroxide molecule as a model of the electronic switch which may be of interest to molecular electronics. It is shown that the peroxide molecule has two well-defined steady states with a sufficiently long lifetime and it is well managed for a possible transference to either of the two well-defined states of the system. These properties of molecules can be used for the modeling of nanoelectronic circuitry. [ABSTRACT FROM AUTHOR]

We study the effect of polyethylene glycol (PEG) on the dynamic and structure of water droplets at the reverse sodium bis-(2-ethylhexyl) sulfosuccinate (AOT) microemulsion. The mixture of water and oil with anionic surfactant AOT can form microemulsion. The dynamic of microemulsion in the presence of PEG is investigated by photon correlation spectroscopy technique. We mainly focus on the variation of the translational diffusion behaviour as a function of the polymer concentration and polymer length scale. By increasing the content of the lowest PEG length scale (Mn= 285), the dynamic of microemulsion slows down. In addition, one relaxation process is distinguished for all polymer concentration. However, for the two higher polymer length scale (Mn= 2200 and 6000), two relaxations are observed and the dynamic of microemulsion speeds up. We used the small angle X-ray scattering technique to monitor the size and the polydispersity of the mixture system (AOT microemulsion/PEG). [ABSTRACT FROM AUTHOR]

Abstract: The most important quantities referred to transport phenomena in nanostructures are well described by the Drude–Lorentz model and generalizations. I have presented a new “time-domain” Drude–Lorentz-like model for nano-transport and its quantum generalization; the model is general and offers good fitting using experimental data obtained from scientific literature. It allows interesting applications in the field of nanostructured materials, also in the biological and medical fields. I consider in this paper the elaboration of experimental data of SWCN; implemented data offer interesting details regarding the influence of temperature for velocity and diffusivity in transparent carbon nanotube films. [Copyright &y& Elsevier]

The interaction between doped graphene nanoislands connected by narrow junctions constitutes an ideal testbed to probe quantum effects in plasmonic systems. Here, the interaction between graphene plasmons in neighboring nanoislands is predicted to be extremely sensitive to the size and shape of the junctions. The reported ab initio calculations reveal three different regimes of interaction: (1) for narrow bridges (<4 carbon-atom rows), the conductance of the junction is too low to allow electron transport and the optical response is dominated by a characteristic bonding dipolar dimer mode that also appears in a classical description; (2) for wider junctions (4-8 carbon rows), a strong charge polarization is induced across the junction, which gives rise to a novel junction plasmon that has no counterpart in a classical description; (3) for even wider junctions (≥8 rows), their conductance is sufficiently large to allow charge transport between the two graphene islands, resulting in a pronounced charge-transfer plasmon, which can also be described classically. This work opens a new path for the investigation of intrinsic plasmon quantum effects. [ABSTRACT FROM AUTHOR]

Based on the analysis of a range of key publications in the area of nanoenergy, which, among other journals, were reflected in the Physics of Nanoobjects and Nanotechnology issue of the peer-reviewed journal that was published by the All-Russia Institute of Scientific and Technical Information of the Russian Academy of Sciences (VINITI RAS) in the 2000-2012 period, key areas of research in this field are analyzed from the perspective of physics. The citation indexes of the key publications, the geographic origins of their authors, and the demand for nanoenergy products are presented. The areas of growth are specified, and the scientific interest in the related problems in different countries is analyzed. [ABSTRACT FROM AUTHOR]

We consider various effects that are encountered in matter wave interference experiments with massive nanoparticles. The text-book example of far-field interference at a grating is compared with diffraction into the dark field behind an opaque aperture, commonly designated as Poisson's spot or the spot of Arago. Our estimates indicate that both phenomena may still be observed in a mass range exceeding present-day experiments by at least two orders of magnitude. They both require, however, the development of sufficiently cold, intense and coherent cluster beams. While the observation of Poisson's spot offers the advantage of non-dispersiveness and a simple distinction between classical and quantum fringes in the absence of particle wall interactions, van der Waals forces may severely limit the distinguishability between genuine quantum wave diffraction and classically explicable spots already for moderately polarizable objects and diffraction elements as thin as 100 nm. [ABSTRACT FROM AUTHOR]

A comparative analysis of the thematic scope of publications in the literature focusing on graphene in the period between 2010 and the first half of 2011 is conducted. The development patterns for physics of graphene are highlighted. Hotspots and emerging trends are outlined in this area, based on the analysis of publications in volumes 1-12 of the 2010 edition and volumes 1-6 of the 2011 edition of the peer-reviewed journal The Physics of Nanoobjects and Nanotechnologies published by the All Union Institute for Scientific and Technical Information of the Russian Academy of Sciences (VINITI RAS). [ABSTRACT FROM AUTHOR]

This is a brief information and analytical survey of the papers that were submitted to the Third International Nanotechnology Forum that was held in Moscow on November 1-3, 2010. Scientometric data on the participants, their origins by region and research center, as well as an analysis of the achievements and problems of Russian research on nanotechnologies, are given. [ABSTRACT FROM AUTHOR]

This is a brief information and analytical survey of the papers submitted to the Second International Nanotechnology Forum held in Moscow in October 2009. Scientometric data on the participants, their origins by regions and research centers, as well as an analysis of the advancements and problems of Russian research in nanotechnologies, are given. [ABSTRACT FROM AUTHOR]

This is a brief information-analytical review of papers submitted on the First International Forum on Nanotechnologies held in Moscow in December 2008. Scientometric data on the participants, their origin by region and research center and analysis of advancements and problems of Russian studies on nanotechnology are discussed. [ABSTRACT FROM AUTHOR]

Abstract: We consider a quantum system consisting of a regular chain of elementary subsystems with nearest neighbor interactions and assume that the total system is in a canonical state with temperature . We analyze under what condition the state factors into a product of canonical density matrices with respect to groups of subsystems each, and when these groups have the same temperature . While in classical mechanics the validity of this procedure only depends on the size of the groups , in quantum mechanics the minimum group size also depends on the temperature . As examples, we apply our analysis to a harmonic chain and an Ising spin chain. We discuss various features that show up due to the characteristics of the models considered. For the harmonic chain, which successfully describes thermal properties of insulating solids, our approach gives a first quantitative estimate of the minimal length scale on which temperature can exist: this length scale is found to be constant for temperatures above the Debye temperature and proportional to below. [Copyright &y& Elsevier]

In this paper, a fine particle manipulation system using a piezoresistive microcantilever, which is normally utilized in Atomic Force Microscopy, as the manipulator and force sensor, and a top-view Optical Microscope (OM) as the vision sensor is proposed. Modeling and control of the interaction forces among the manipulator, particle and surface have been realized for moving particles with sizes less than 3 μm on a silicon substrate in 2D. The microcantilever behaves also as a force sensor which enables contact point detection, real-time force measurements, and surface alignment sensing. A 2D OM real-time image feedback constitutes the main user interface, where the operator uses mouse cursor and keyboard for defining the tasks for the cantilever motion controller. Preliminary particle manipulation experiments are demonstrated for 2.02 and 1 μm gold-coated latex particles, and it is shown that the system can be utilized in 2D micro particle assembling. [ABSTRACT FROM AUTHOR]