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The interplay of topology, magnetism, and correlations gives rise to intriguing phases of matter. In this study, through state-of-the-art angle-resolved photoemission spectroscopy, density functional theory, and dynamical mean-field theory calculations, we visualize a fourfold degenerate Dirac nodal line at the boundary of the bulk Brillouin zone in the antiferromagnet YMn2Ge2. We further demonstrate that this gapless, antiferromagnetic Dirac nodal line is enforced by the combination of magnetism, space-time inversion symmetry, and nonsymmorphic lattice symmetry. The corresponding drumhead surface states traverse the whole surface Brillouin zone. YMn2Ge2 thus serves as a platform to exhibit the interplay of multiple degenerate nodal physics and antiferromagnetism. Interestingly, the magnetic nodal line displays a d-orbital dependent renormalization along its trajectory in momentum space, thereby manifesting Hund's coupling. Our findings offer insights into the effect of electronic correlations on magnetic Dirac nodal lines, leading to an antiferromagnetic Hund nodal line. The interplay of magnetism, various symmetries and correlations can lead to intriguing physics in the solid state. Here, the authors report signatures of a Hund nodal line in the antiferromagnet YMn2Ge2. [ABSTRACT FROM AUTHOR]

The kagome lattice is an exciting solid state physics platform for the emergence of nontrivial quantum states driven by electronic correlations: topological effects, unconventional superconductivity, charge and spin density waves, and unusual magnetic states such as quantum spin liquids. While kagome lattices have been realized in complex multi-atomic bulk compounds, here we demonstrate from first-principles a process that we dub kagomerization, in which we fabricate a two-dimensional kagome lattice in monolayers of transition metals utilizing an hexagonal boron nitride (h-BN) overlayer. Surprisingly, h-BN induces a large rearrangement of the transition metal atoms supported on a fcc(111) heavy-metal surface. This reconstruction is found to be rather generic for this type of heterostructures and has a profound impact on the underlying magnetic properties, ultimately stabilizing various topological magnetic solitons such as skyrmions and bimerons. Our findings call for a reconsideration of h-BN as merely a passive capping layer, showing its potential for not only reconstructing the atomic structure of the underlying material, e.g. through the kagomerization of magnetic films, but also enabling electronic and magnetic phases that are highly sought for the next generation of device technologies. Using first-principles calculations, the authors highlight h-BN's role in reshaping transition metal monolayers into kagome lattices—a key structure in 2D physics—and in stabilizing topological solitons vital for advanced data storage solutions. [ABSTRACT FROM AUTHOR]

Definition: The Pandemic Equation describes multiple pandemic waves and has been applied to describe the COVID-19 pandemic. Using the generalized approaches of solid-state physics, we derive the Pandemic Equation, which accounts for the effects of pandemic mitigation measures and multiple pandemic waves. The Pandemic Equation uses slow and fast time scales for "curve flattening" and describing vaccination and mitigation measures and the Scaled Fermi–Dirac distribution functions for describing transitions between pandemic waves. The Pandemic Equation parameters extracted from the pandemic curves can be used for comparing different scenarios of the pandemic evolution and for extrapolating the pandemic evolution curves for the periods of time on the order of the instantaneous Pandemic Equation characteristic time constant. The parameter extraction for multiple locations could also allow for uncertainty quantification for such pandemic evolution predictions. [ABSTRACT FROM AUTHOR]

A comprehensive physical electro-thermal modeling approach is explored to investigate the intricate mechanisms underlying filament formation and the effect of surface perturbation in nanoscale Y2O3-based memristors. The approach integrates fundamental principles of solid-state physics, electrochemistry, and materials science to develop a detailed physical model that captures the key phenomena governing the operation of Y2O3 memristors. The simulation is carried out in a semiconductor physics-based tool, i.e., COMSOL Multiphysics with a defined MATLAB script, wherein simulation is based on the minimum free energy of the used materials at an applied input voltage. The fundamental processes in filament growth include ion migration, redox reactions, and vacancy dynamics within the Y2O3 lattice. Furthermore, the influence of surface perturbation on the overall device behavior, grain boundaries, and electrode interactions impact on memristor performance is also investigated. The surface perturbations significantly influenced the switching dynamics of the memristor, including variations in switching voltages, ON/OFF current ratio, filament radius, and filament temperature during the switching process. Therefore, the presented findings contribute to a deeper understanding of the physical mechanisms at play in Y2O3 memristors, offering valuable guidance for the design and engineering of these nanoscale devices for next-generation memory and neuromorphic computing applications. This physical modeling approach not only enhances our comprehension of memristor behavior but also paves the way for the development of more efficient and reliable memristor-based technologies. [ABSTRACT FROM AUTHOR]

Featured Application: The findings presented in this work will allow the calculation of the electronic density states as well as the electrical and optical properties of complex one-dimensional coupled periodic potential wells without using expensive licensed software. The analytical generalization for N periodic potential wells coupled to a probe rectangular-like potential and a zero potential is extremely important in the study of one-dimensional periodic potentials in solid state physics, e.g., in the calculation of transport, optical, and magnetic properties. These findings raise the possibility of calculating equations for the generalization of N arbitrary potentials related to any potential V (x) using special functions as a solution. In this work, a novel analytical generalization of the transcendental energy equation, group velocity, and effective mass for N-coupled potentials to a probe one-dimensional potential V = V (x) was proposed. Initially, two well-known linear periodic potentials V = V (x) were employed to obtain analytical solutions for rectangular-like and Dirac-delta potentials. Python libraries were used to easily represent the equations for one or two rectangular-like potentials coupled with an arbitrary potential, highlighting the transcendental energy, group velocity, and effective mass. The results showed that the group velocity behavior changed its orientation due to the sign of the potential, whereas the width of the potential V (x) strongly influenced the group velocity behavior. The effective mass was also modified by the potential shapes, and their combinations, both effective mass and group velocity, exhibited similar physical behaviors to those found in ordinary rectangular-like potentials. [ABSTRACT FROM AUTHOR]

Textbooks often present the phenomenon of screening within the Thomas–Fermi model for three-dimensional free electron gases, but obtaining the dielectric response function and screening potential for dielectric systems of reduced dimensionality is also of pedagogical interest. In this work, we introduce a simple approach to investigate static screening in dielectric systems in the presence of an impurity charge for different dimensionalities. This approach is applicable to semiconductors and insulators alike. We demonstrate that, in 3D systems, the macroscopic dielectric function in reciprocal space is a constant, while in 2D and 1D systems, it strongly depends on the momentum transferred to the electrons in the dielectric. Through the proposed dielectric screening model, one can also determine binding energies in a hydrogenic model that can be used to describe excitations in real semiconductor systems. Screening in dielectrics is a measure of the strength of Coulomb interactions. Because of the reduced dimensionality, screening is hampered in 2D or quasi-1D materials, with important consequences in nanometer-scale systems that are currently important to the condensed matter community. This paper explains why reduced dimensionality reduces the screening. The topic is appropriate for undergraduate electromagnetism classes or advanced condensed matter courses. [ABSTRACT FROM AUTHOR]

Charge density waves (CDWs) involved with electronic and phononic subsystems simultaneously are a common quantum state in solid-state physics, especially in low-dimensional materials. However, CDW phase dynamics in various dimensions are yet to be studied, and their phase transition mechanism is currently moot. Here we show that using the distinct temperature evolution of orientation-dependent ultrafast electron and phonon dynamics, different dimensional CDW phases are verified in CuTe. When the temperature decreases, the shrinking of c-axis length accompanied with the appearance of interchain and interlayer interactions causes the quantum fluctuations (QF) of the CDW phase until 220 K. At T < 220 K, the CDWs on the different ab-planes are finally locked with each other in anti-phase to form a CDW phase along the c-axis. This study shows the dimension evolution of CDW phases in one CDW system and their stabilized mechanisms in different temperature regimes. Some materials host multiple charge density wave states, however, their dynamics and the nature of phase transitions are often unclear. Here, using temperature and orientation resolved ultrafast spectroscopy, the authors reveal charge density waves of different dimensionality in CuTe and elucidate their mechanism. [ABSTRACT FROM AUTHOR]

The document titled "Advanced Inorganic Semiconductor Materials" is a summary of a special issue that explores current research and ideas in the field of inorganic semiconductors. The issue includes nine articles and two topical reviews that cover various topics, such as 2D materials, quantum dots, avalanche photodiodes, and perovskites. Each article delves into different aspects of these materials, including their optical, mechanical, and electronic properties, as well as their potential applications in optoelectronic devices. The findings presented in the articles contribute to the understanding and development of advanced inorganic semiconductor materials for various applications. The document expresses gratitude to the contributors and reviewers for their valuable contributions to the special issue. [Extracted from the article]

The solution of a quantum periodic potential in solid state physics is relevant because one can understand how electrons behave in a corresponding crystal. In this paper, the analytical solution of the energy formulation for a one-dimensional periodic potential that meets certain boundary conditions is developed in a didactic and detailed way. In turn, the group speed and effective mass are also calculated from the transcendental energy equation of a potential V = V (x) . From this, a comparison is made with periodic potentials with known analytical solutions, such as the Dirac delta, as well as rectangular and triangular potentials. Finally, some limits are proposed in which these periodic potentials of the form V = V (x) approach the periodic Dirac delta potential of positive intensity. Therefore, the calculations described in this paper can be used as the basis for more-complex one-dimensional potentials and related simulations. [ABSTRACT FROM AUTHOR]

Specific properties of quantum field theory are described by considering the combination of the system under investigation and the cloud of virtual or real particles associated with the field. Such a structure is called a "dressed system", in contrast with the bare one in the absence of the interaction with the field. The description of the properties of such clouds in various physical situations is, today, an active research area. Here, we present the main features associated with virtual and real dressings, focusing on photon dressing. In analogy to virtual photon clouds dressing electrons in vacuum, virtual phonon clouds appear in solid-state physics. The interaction between real photons and the schematized two-level structure of an atom paves the way to flexible quantum control. Here, a unifying Floquet engineering approach is applied to describe single- and multiple-dressed atom configurations. Connections with the past and present atomic physics experiments are presented. [ABSTRACT FROM AUTHOR]

Solid-state physics has important applications in the development of modern technologies. Although solid-state concepts, such as electric and thermal conductivity, are included in the curricula at all educational levels, even university students have many incorrect ideas about them. The incorrect ideas identified in previous studies are mainly related to macroscopic aspects of solid-state physics. With the aim of gaining a more comprehensive insight into students' understanding of solid-state physics, we have developed a multiple-choice concept inventory on microscopic models of electric and thermal conductivity of solids (METCS). The inventory has been field-tested with a sample consisting of 233 first-year medical faculty and engineering students from the University of Rijeka (Croatia). METCS proved to have good psychometric features and it helped to uncover many incorrect ideas that have not been reported in the earlier physics education literature. The findings from this study could be a good starting point for the development of evidence-based, university-level tutorials on microscopic models of electric and thermal conductivity. [ABSTRACT FROM AUTHOR]

This document is an editorial introducing a special issue of the journal Magnetochemistry. The special issue focuses on research related to magnetic and magnetoelectric materials. The editorial acknowledges the contributions of various authors and their research topics, including investigations of thin films, superconductors, nanocomposites, and spinel compounds. The authors express gratitude to the editorial team and declare no conflicts of interest. [Extracted from the article]

In the current research, we consider the solution of dispersion relations addressed to solid state physics by using artificial neural networks (ANNs). Most specifically, in a double semiconductor heterostructure, we theoretically investigate the dispersion relations of the interface polariton (IP) modes and describe the reststrahlen frequency bands between the frequencies of the transverse and longitudinal optical phonons. The numerical results obtained by the aforementioned methods are in agreement with the results obtained by the recently published literature. Two methods were used to train the neural network: a hybrid genetic algorithm and a modified version of the well-known particle swarm optimization method. [ABSTRACT FROM AUTHOR]

In this study, carbon fiber reinforced polymer matrix composites were produced to investigate the trigger effect on energy absorption performance. Production was carried out by vacuum infusion method. Three types of trigger geometry were opened on the composite crash boxes produced and also comparison sample without trigger was prepared. The quasi-static compression tests of these four different samples were carried out and the energy absorption performances of the samples were evaluated with the obtained data. In addition, the damages of the samples were examined, and it was revealed how they changed with the trigger. Accordingly, the sample described as S-2, (the triggered sample, which consists of four symmetrical slits downwards from its upper surface) exhibited the best performance in terms of absorbed energy. Additionally, the peak forces were reduced with the triggers opened and the maximum peak force decreases were seen in S-3(with hole type triggers) and S-4 (with horizontal slit type triggers) samples. [ABSTRACT FROM AUTHOR]

A crucial step in developing new and/or more efficient devices relies on the detailed knowledge of the properties of their main (elemental or combined) parts. The same applies to titanium dioxide TiO2 that forms the basis of today numerous applications whose performances are determined by the presence or relative amount of the Anatase (A-) and Rutile (R-) most common phases of TiO2. Whereas the basic structural characteristics of these two polymorphs are very well-established, some of their optical aspects still deserve attention. With these ideas in mind this work presents a comprehensive investigation of the optical bandgap Egap of TiO2 under the Anatase and Rutile phases. The study considered pure A-TiO2 and R-TiO2 samples in the form of powder, and optical reflectance and Raman spectroscopy in the 83–823 K temperature range. In addition to reliable Egap values the study explores their temperature-dependent Egap(T) behavior that is expected to assist future advancements in the field of TiO2-based materials and devices (thin films, interfaces, low-dimensional systems, and photocatalytic and solar cells, for example).

The article focuses on the Nobel Prize in Chemistry 2023 awarded to Aleksey Yekimov, Louis E. Brus, and Moungi G. Bawendi for their discovery and synthesis of quantum dots. Topics include the history of quantum size effects, the pioneering experiments in the 1970s, the independent work of Yekimov and Brus in the 1980s, and the subsequent breakthroughs by Bawendi in the 1990s, leading to the widespread applications of quantum dots in scientific research and commercial products.

Peierls transition that modifies electronic band structure has attracted intensive attention in solid state physics. In the present work, we report that a photonic analog of Peierls transition has been observed in a 1-D triangular metal diaphragm array, where the photonic bandgap structures have been designed at will by adjusting periodically metal diaphragm positions. It is shown by the numerical analysis that the transmission and radiation effect of the present periodic metal structure designed through the Peierls transition rule exhibits the behavior significantly different from an original periodic structure with each unit cell containing a metal diaphragm. The near- and far-field measurement results are in good agreement with our theoretical simulation. The present effect of photonic Peierls transition can serve as a working mechanism for designing new types of guided wave devices. It can be seen that the photonic Peierls transition would be one of the simplest ways for modifying the transport characteristics of electromagnetic waves in periodic structures. [ABSTRACT FROM AUTHOR]

Tavis-Cummings (TC) cavity quantum electrodynamical effects, describing the interaction of N atoms with an optical resonator, are at the core of atomic, optical and solid state physics. The full numerical simulation of TC dynamics scales exponentially with the number of atoms. By restricting the open quantum system to a single excitation, typical of experimental realizations in quantum optics, we analytically solve the TC model with an arbitrary number of atoms with linear complexity. This solution allows us to devise the Quantum Mapping Algorithm of Resonator Interaction with N Atoms (Q-MARINA), an intuitive TC mapping to a quantum circuit with linear space and time scaling, whose N+1 qubits represent atoms and a lossy cavity, while the dynamics is encoded through 2N entangling gates. Finally, we benchmark the robustness of the algorithm on a quantum simulator and superconducting quantum processors against the quantum master equation solution on a classical computer. [ABSTRACT FROM AUTHOR]

Professor Sergey Alekseevich Pikin, a renowned theoretical physicist, passed away at the age of 82. He made significant contributions to condensed matter physics, specifically in the field of liquid crystals. His research focused on various aspects of liquid crystals, including structural phase transitions, electro-hydrodynamics, orientational turbulence, and thermodynamics. Professor Pikin collaborated with experimental colleagues, published a monograph on structural transformations in liquid crystals, and developed theories on flexoelectricity, phase transitions in chiral smectics C, molecular motors, and multiferroics. He was highly respected by his peers and will be greatly missed by the scientific community. Additionally, Professor Pikin had a deep appreciation for his family, art, and music. [Extracted from the article]

Introduction/purpose: Quantum field theory techniques are able to describe precisely, inter alia, collective phenomena of statistical and solid state physics. Method: The path integral method with a Wick rotation shows its complete analogy with the partition function of statistical mechanics. Results: The Landau–Ginzburg phenomenology successfully describes collective phenomena such as spontaneous magnetization and superconductivity. Conclusions: Symmetry breaking phenomena could give macroscopic results. [ABSTRACT FROM AUTHOR]

Introductory textbooks in solid state physics present solvable models for illustrating the occurrence of allowed bands and forbidden gaps in the energy spectrum of Bloch electrons. However, the quantum mechanical description of electrons in non-periodic solids, such as amorphous materials, is beyond the scope of introductory courses because of its intrinsic complexity. The tight-binding approximation can account for such a scenario by letting the atomic levels vary at random from lattice site to site. We theoretically tackle the study of the average properties of the energy spectrum by introducing a transfer matrix method that allows us to obtain closed expressions for the so-called coherent potential. The coherent potential is energy-dependent and constant in space. It replaces the actual atomic random potential, thus generating a periodic effective medium with the same average properties as the non-periodic solid. We demonstrate that the average density of states can be calculated within this framework without relying on heavy mathematical machinery. Thus, our approach is suitable for introductory courses in solid state physics and materials science. [ABSTRACT FROM AUTHOR]

Polar sea ice is a critical component of Earth's climate system. As a material, it is a multiscale composite of pure ice with temperature-dependent millimeter-scale brine inclusions, and centimeter-scale polycrystalline microstructure which is largely determined by how the ice was formed. The surface layer of the polar oceans can be viewed as a granular composite of ice floes in a sea water host, with floe sizes ranging from centimeters to tens of kilometers. A principal challenge in modeling sea ice and its role in climate is how to use information on smaller-scale structures to find the effective or homogenized properties on larger scales relevant to process studies and coarse-grained climate models. That is, how do you predict macroscopic behavior from microscopic laws, like in statistical mechanics and solid state physics? Also of great interest in climate science is the inverse problem of recovering parameters controlling small-scale processes from large-scale observations. Motivated by sea ice remote sensing, the analytic continuation method for obtaining rigorous bounds on the homogenized coefficients of two-phase composites was applied to the complex permittivity of sea ice, which is a Stieltjes function of the ratio of the permittivities of ice and brine. Integral representations for the effective parameters distill the complexities of the composite microgeometry into the spectral properties of a self-adjoint operator like the Hamiltonian in quantum physics. These techniques have been extended to polycrystalline materials, advection diffusion processes, and ocean waves in the sea ice cover. Here we discuss this powerful approach in homogenization, highlighting the spectral representations and resolvent structure of the fields that are shared by the two-component theory and its extensions. Spectral analysis of sea ice structures leads to a random matrix theory picture of percolation processes in composites, establishing parallels to Anderson localization and semiconductor physics and providing new insights into the physics of sea ice. [ABSTRACT FROM AUTHOR]

Due to the increasing number of internal combustion engine vehicles, fossil fuel sources have decreased drastically in the last century. In addition, the concerns about global warming caused by vehicle emissions have led automotive manufacturers to search for new alternatives to transport. Quadricycles have started to be seen as future transport vehicles due to their smaller design and lower energy consumption when compared to conventional vehicles. Furthermore, they are also considered to prevent increasing traffic jams in metropolitan areas. The lightweight design of a quadricycle is crucial since its weight would affect energy consumption. On the other hand, because of their minimalistic design, crashworthiness is another factor that must be considered in the structural design of quadricycles for the safety of occupants in case of a collision. Composites are one of the most promising materials for manufacturing lightweight structures due to having a high strength-to-weight ratio compared to conventional metals. In this study, different body designs and optimizations of quadricycles are introduced. Comparisons are made between conventional metals and composite materials used in quadricycles in terms of weight and stiffness. Studies showed that a 15% increase in specific energy absorption capability and a 50% weight reduction at the same time is possible by using composite materials rather than metals in the design of structural parts. [ABSTRACT FROM AUTHOR]

Researchers and scientists were inspired by the enormous reactions from industry about heat transformation enhancements due to the entropy generation. The entropy generation shows as a extremes for complex mechanisms like solid state physics, two-phase flows, electro-magnetic air conditioning, and economic evaluation of manufacturing processes, as well as biological technologies chemistry, including biochemistry. We note here that many thermal mechanisms are related to the irreversibility system. The current work focused on the entropy generation impacts in viscous magnetized mono-nanofluids flow between stretchable rotating disks. Ferro and copper are considered as nanoparticles and Blood as a base fluid. The Darcy-Forchheimer porous medium and joule heating effects are considered. For simplifying the current analysis, suitable transformation were introduced in the mathematical description to renovate the partial differential equations (PDE's) into coupled ordinary ones. To solve the resulting ODEs well-known numerical algorithm bvp4c is used in Matlab in the light of Lobatto-IIIA formula. The consequence of sundry parameters against velocity components, pressure field, temperature distribution and entropy generation are described graphically. [ABSTRACT FROM AUTHOR]

The quantum Hall effect is widely used for the investigation of fundamental phenomena, ranging from topological phases to composite fermions. In particular, the discovery of a room temperature resistance quantum in graphene is significant for compact resistance standards that can operate above cryogenic temperatures. However, this requires large magnetic fields that are accessible only in a few high magnetic field facilities. Here, we report on the quantum Hall effect in graphene encapsulated by the ferroelectric insulator CuInP2S6. Electrostatic gating of the graphene channel enables the Fermi energy to be tuned so that electrons in the localized states of the insulator are in equilibrium with the current-carrying, delocalized states of graphene. Due to the presence of strongly bound states in this hybrid system, a quantum Hall plateau is observed over a wide range of temperatures in relatively modest magnetic fields. The quantum Hall effect has had a profound impact on solid-state physics and has been investigated using different two-dimensional systems, including graphene. Here, the authors investigate graphene encapsulated by a ferroelectric insulator, CuInP2S6, where they observe a quantum Hall effect that endures over a wide temperature range in relatively modest magnetic fields. [ABSTRACT FROM AUTHOR]

Summary: The halide lead perovskite single crystals (HLPSCs) have great potential in gamma-ray detection with high attenuation coefficient, strong defects tolerance, and large mobility-lifetime product. However, mobile halide ions would migrate under high external bias, which would both weaken the gamma-ray response and cause additional noise. Here, we report the gamma-ray PIN photodiodes made of cascade HLPSCs including both ion-formed and electron-hole-formed electrical junctions that could suppress the ions migration and improve the charges collection. Our photodiodes based on cascade HLPSCs (MAPbBr3/MAPbBr2.5Cl0.5/MAPbCl3) show a wide halide-ion-formed depletion layer of ∼52 μm. The built-in potential along the wide ionic-formed junction ensures a high mobility-lifetime product of 1.1 × 10−2 cm2V−1. As a result, our gamma-ray PIN photodiodes exhibit compelling response to 241Am, 137Cs, and 60Co; the energy resolution can reach 9.4%@59.5keV and 5.9%@662keV, respectively. This work provides a new path toward constructing high-performance gamma-ray detectors based on HLPSCs.

Crystal structure predictions based on first-principles calculations have gained great success in materials science and solid state physics. However, the remaining challenges still limit their applications in systems with a large number of atoms, especially the complexity of conformational space and the cost of local optimizations for big systems. Here, we introduce a crystal structure prediction method, MAGUS, based on the evolutionary algorithm, which addresses the above challenges with machine learning and graph theory. Techniques used in the program are summarized in detail and benchmark tests are provided. With intensive tests, we demonstrate that on-the-fly machine-learning potentials can be used to significantly reduce the number of expensive first-principles calculations, and the crystal decomposition based on graph theory can efficiently decrease the required configurations in order to find the target structures. We also summarized the representative applications of this method on several research topics, including unexpected compounds in the interior of planets and their exotic states at high pressure and high temperature (superionic, plastic, partially diffusive state, etc.); new functional materials (superhard, high-energy-density, superconducting, photoelectric materials), etc. These successful applications demonstrated that MAGUS code can help to accelerate the discovery of interesting materials and phenomena, as well as the significant value of crystal structure predictions in general. [ABSTRACT FROM AUTHOR]

In the current research, we consider the solution of dispersion relations addressed to solid state physics by using artificial neural networks (ANNs). Most specifically, in a double semiconductor heterostructure, we theoretically investigate the dispersion relations of the interface polariton (IP) modes and describe the reststrahlen frequency bands between the frequencies of the transverse and longitudinal optical phonons. The numerical results obtained by the aforementioned methods are in agreement with the results obtained by the recently published literature. Two methods were used to train the neural network: a hybrid genetic algorithm and a modified version of the well-known particle swarm optimization method.

Non-linear evolution equations play a prominent role in describing a wide range of phenomena in optical fibers, fluid dynamics, electromagnetic radiation, plasma and solid state physics. An important category of non-linear evolution models that characterizes shallow wave phenomena are the Korteweg-de Vries (KdV) models. In this regard, time-fractional Korteweg-de Vries models of seventh order are the main focus of this research. A general KdV seventh-order equation is considered with different coefficients to form Lax, Kaup–Kuperschimdt and Sawada–Kotera–Ito KdV models. An efficient semi-analytical algorithm named as He-Laplace (HLM) is applied for the solution of these models. In this algorithm, Laplace transform is hybrid with homotopy perturbation method (HPM). This study provides important results as non-linear evolution seventh-order models in fractional sense have not been captured through HLM in current literature. Absolute errors are computed and compared with already existing results to confirm the superiority of proposed algorithm over other existing techniques. Numerical and graphical investigations are conducted to evaluate the approximate series form solutions. The dynamic behavior of fractional parameter is observed by calculating residual errors and plotting two dimensional diagrams throughout the fractional-domain. Analysis confirms that the proposed methodology provides an effective and convenient way for solving fractional KdV models. [ABSTRACT FROM AUTHOR]

Sodium potassium niobate, Na1-zKzNbO3, is a ceramic material that exhibits dielectric and piezoelectric properties, which can be tuned by changing the composition of the material. The dielectric properties of Na1-zKzNbO3 ceramics are characterized by a high dielectric constant and low loss, which makes them useful for applications in capacitors, filters, and resonators. Pellets of Na1-zKzNbO3 (0.120 ≤ z ≤ 0.210) were prepared by the solid-state reaction technique. The structural and morphological study was carried out on the prepared compositions at room temperature (RT). A Piezoelectric indirect constant (d33*) was obtained for the prepared compositions. Additionally, dielectric measurements were performed at frequencies 10-1000 kHz, from ambient temperature to 500°C. For the prepared compositions with z = 0.175, a break in the XRD peak shifting patterns was observed, and the average grain size was calculated at 2.044 ± 0.3 μm. Also, the maximum indirect piezoelectric constant (d33*) was observed for z = 0.175 among the prepared compositions. For the prepared compositions, compositions with z = 0.140 showed the highest dielectric constant (peak value 1486, 385°C). Among the prepared samples, dielectric constant (ε), loss tangent (tan δ) and electric conductivity (σ) were found to be minimum for the composition with z = 0.175 at all the measured frequencies. Anomalous dielectric, piezoelectric and structural properties are evident for the samples with z = 0.175 among the prepared samples. Overall, the composition-dependent dielectric and piezoelectric properties of Na1-zKzNbO3 ceramics make them promising materials for use in various electronic and sensing applications where high-performance dielectric and piezoelectric materials are required. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of soft barriers installed in the ground for screening shear and compression waves in saturated and dry grounds. The proposed barriers include the soil as a core surrounded by a soft material like foam. The barriers are arranged in periodic structures, and it is aimed to find their bandgaps using solid-state physics theories. Firstly, an ideal infinite lattice is considered, and its bandgaps and attenuation zones are found using Bloch–Floquet theory. Thereafter, a finite lattice of barriers is also investigated for practical purposes, and the minimum required number of barrier rows to obtaining similar bandgaps is obtained. The infinite and finite lattices are simulated using finite element COMSOL Multiphysics software with its inbuilt features. Also, the analyses are performed in dry and saturated grounds using elastodynamic and Biot's poroelastodynamic theories, respectively. Extensive parametric studies are also conducted on the material and geometric properties of the barriers, and the corresponding bandgap properties are discussed. The finite element simulations are performed in both frequency and time domains. The obtained results indicate the effectiveness of using soft barriers around the soil in a unit cell for screening the waves in dry and saturated grounds. [ABSTRACT FROM AUTHOR]

At the same time, Lev Blinov maintained a close interaction with the LC laboratory at the Institute of Crystallography in Moscow and actively participated in the work on lasing in LCs. The results of the studies on LCs were summarised in Blinov's first monograph "Electrooptical and magnetooptical properties of liquid crystals" issued by the Moscow Publisher "Nauka" in 1978. In Blinov's laboratory work was carried out on anchoring energy studies of nematic LCs with substrates, various electro-optical effects and the "guest-host" effect in LCs with dichroic dyes. Since the mid-1980s, Lev Blinov became deeply involved in the physics of LC surfaces and studies of the anchoring energy I W i of nematic LCs within confining substrates. [Extracted from the article]

Microwave dielectric materials have been attracted enormous attention for their application in microwave communication. A new microwave dielectric material with composition Zn8/5Al4/15TiO4 was synthesized by conventional solid-state reaction method. The structure of Zn8/5Al4/15TiO4 was refined with the cubic P4332 space group (number of formula unit per unit cell, Z = 4). The Rietveld refinement study revealed the theoretical density ρ = 4.80 g/cm³ and lattice parameter a = 8.405 Å. This compound was crystallized in cubic spinel structure and 1:3 ordering was observed on the octahedral sites. Raman spectrum of the compound was collected at room temperature. Theoretical Factor group analysis for this compound predicts 40 Raman modes and 22 IR modes. However, experimentally 13 vibrational modes have been observed in the Raman spectrum which can be separated into internal TiO6 vibration and external rotation and translation TiO6 modes. Raman modes in the range of 500-800 cm-1 are assigned to internal vibrational modes. [ABSTRACT FROM AUTHOR]

The strange metal behavior, usually characterized by a linear-in-temperature (T) resistivity, is a still unsolved mystery in solid-state physics. It is often associated with the proximity to a quantum critical point (a second order transition at temperature T = 0 , leading to a broken symmetry phase) focusing on the related divergent order parameter correlation length. Here, we propose a paradigmatic shift, focusing on a divergent characteristic time scale due to a divergent dissipation acting on the fluctuating critical modes while their correlation length stays finite. To achieve a divergent dissipation, we propose a mechanism based on the coupling between a local order parameter fluctuation and electron density diffusive modes that accounts both for the linear-in-T resistivity and for the logarithmic specific heat versus temperature ratio C V / T ∼ log (1 / T) , down to low temperatures. [ABSTRACT FROM AUTHOR]

We present an optimization method for the assignment of photometric galaxies to a chosen set of redshift bins. This is achieved by combining simulated annealing, an optimization algorithm inspired by solid-state physics, with an unsupervised machine learning method, a self-organizing map (SOM) of the observed colours of galaxies. Starting with a sample of galaxies that is divided into redshift bins based on a photometric redshift point estimate, the simulated annealing algorithm repeatedly reassigns SOM-selected subsamples of galaxies, which are close in colour, to alternative redshift bins. We optimize the clustering cross-correlation signal between photometric galaxies and a reference sample of galaxies with well-calibrated redshifts. Depending on the effect on the clustering signal, the reassignment is either accepted or rejected. By dynamically increasing the resolution of the SOM, the algorithm eventually converges to a solution that minimizes the number of mismatched galaxies in each tomographic redshift bin and thus improves the compactness of their corresponding redshift distribution. This method is demonstrated on the synthetic Legacy Survey of Space and Time cosmoDC2 catalogue. We find a significant decrease in the fraction of catastrophic outliers in the redshift distribution in all tomographic bins, most notably in the highest redshift bin with a decrease in the outlier fraction from 57 per cent to 16 per cent. [ABSTRACT FROM AUTHOR]

The article presents a much more generic imaging approach to three-dimensional (3D) morphology reconstructions of isolated faceted nanostructures. In addition to known structural motives with high symmetries, imperfect shapes, and agglomerates that were not previously accessible were retrieved. The results open unexplored routes toward true 3D structure determination of single nanoparticles and 3D movies of ultrafast nanoscale dynamics.

The propagated crystal-field-based quantum atomistic solid-state theory starts the theoretical description of a solid containing open d/f shell atoms from the analysis of charge states and low-energy crystal-field discrete electronic structure of 3d=4f=5f=4d=5d ions. The crystal-field-based description of CeRh2Si2 Kondo-lattice antiferromagnetic intermetallics proves that crystal-field states exist in the compounds' "conducting current". In oxides, the realized cation valency is basically equal to the formal valency from the ionic model. The realized valency can be experimentally verified by having its own finger print in the excitation spectrum. Even weak spin-orbit interactions in 3d ions are responsible for the violation of the Curie-Weiss law at low temperatures, and for the realization of the nonmagnetic state, especially for non-Kramers ions, as it is in the case of Sr2RuO4. The quantum atomistic solid-state theory methodology "From atomic physics to solid-state physics" is very fruitful and offers a consistent picture of transition-metal compounds. [ABSTRACT FROM AUTHOR]

The propagated crystal-field-based quantum atomistic solid-state theory starts the theoretical description of a solid containing open d/f shell atoms from the analysis of charge states and low-energy crystal-field discrete electronic structure of 3d=4f=5f=4d=5d ions. The crystal-field-based description of CeRh2Si2 Kondo-lattice antiferromagnetic intermetallics proves that crystal-field states exist in the compounds' "conducting current". In oxides, the realized cation valency is basically equal to the formal valency from the ionic model. The realized valency can be experimentally verified by having its own finger print in the excitation spectrum. Even weak spin-orbit interactions in 3d ions are responsible for the violation of the Curie-Weiss law at low temperatures, and for the realization of the nonmagnetic state, especially for non-Kramers ions, as it is in the case of Sr2RuO4. The quantum atomistic solid-state theory methodology "From atomic physics to solid-state physics" is very fruitful and offers a consistent picture of transition-metal compounds. [ABSTRACT FROM AUTHOR]

Amorphous materials are also distinguished from crystals by their thermal properties. The structural disorder seems to be responsible both for a significant increase in heat capacity compared to crystals of the same composition, but also for a significant decrease in thermal conductivity. The temperature dependence of thermal conductivity, unusual for common interpretations of solid-state physics, gave rise to a lot of debates. We review in this article different interpretations of thermal conductivity in amorphous materials. We show finally that the temperature dependence of thermal conductivity in dielectric materials can be understood by relating it to the disorder-dependent harmonic vibrational eigenmodes. [ABSTRACT FROM AUTHOR]

The May 2024 issue of the American Journal of Physics features a variety of articles covering topics in physics. These include letters to the editor, a tool for developing inclusive physics textbooks, labor-based grading practices, a modern interpretation of Newton's theorem of revolving orbits, the effects of general relativistic post-Newtonian approximations, seldom-used theorems of vector calculus, screening in solid state physics, the hyperfine interaction in hydrogen, the Born rule in quantum mechanics, statistical physics of frictional grains, an in-fiber Mach-Zehnder strain sensor, an Arduino cavity controller for LIGO analogy lab, a resolution of the trolley paradox, an unorthodox physical solution to a classic puzzle, and a book review on solar power finance. These articles cover a range of topics and can be useful for researchers and students in various physics disciplines. [Extracted from the article]

Metal halide perovskites have drawn substantial interest in optoelectronic devices in the past decade. Perovskite/electrode contacts are crucial for constructing high‐performance charge‐transporting‐layer‐free perovskite devices, such as solar cells, field‐effect transistors, artificial synapses, memories, etc. Many studies have evidenced that the perovskite layer can directly contact the electrodes, showing abundant physicochemical, electronic, and photoelectric properties in charge‐transporting‐layer‐free perovskite devices. Meanwhile, for perovskite/metal contacts, some critical interfacial physical and chemical processes are reported, including band bending, interface dipoles, metal halogenation, and perovskite decomposition induced by metal electrodes. Thus, a systematic summary of the role of metal halide perovskite/electrode contacts on device performance is essential. This review summarizes and discusses charge carrier dynamics, electronic band engineering, electrode corrosion, electrochemical metallization and dissolution, perovskite decomposition, and interface engineering in perovskite/electrode contacts‐based electronic devices for a comprehensive understanding of the contacts. The physicochemical, electronic, and morphological properties of various perovskite/electrode contacts, as well as relevant engineering techniques, are presented. Finally, the current challenges are analyzed, and appropriate recommendations are put forward. It can be expected that further research will lead to significant breakthroughs in their application and promote reforms and innovations in future solid‐state physics and materials science. [ABSTRACT FROM AUTHOR]

The article presents a study which explores about the diabatic and adiabatic transitions between Floquet states imprinted in coherent exciton emission in monolayer WSe2. It mentions that results of the study which provide a previously unexplored approach to Floquet engineering and lead to control of quantum materials through pulse shaping of the driving field.

In solid state physics, phase transitions can influence material functionality and alter their properties. In mechanical metamaterials, structural‐phase transitions can be achieved through instability or buckling of certain structural elements. However, these fast transitions in one mechanical parameter typically affect significantly the remaining parameters, hence, limiting their applications. Here, this limitation is addressed by designing a novel 3D mechanical metamaterial that is capable of undergoing a phase transition from positive to negative Poisson's ratio under compression, without significant degradation of Young's modulus (i.e. the phase transition is elastically‐stable). The metamaterial is fabricated by two‐photon lithography at the micro‐scale and its mechanical behavior is assessed experimentally. For another choice of structural parameters, it is then shown that the auxetic behavior of the considered 3D metamaterial class can be maintained over a wide range of applied compressive strain. [ABSTRACT FROM AUTHOR]