The nanostructures produced by oblique-incidence broad beam ion bombardment of a solid surface are usually modelled by the anisotropic Kuramoto–Sivashinsky equation. This equation has five parameters, each of which depend on the target material and the ion species, energy, and angle of incidence. We have developed a deep learning model that uses a single image of the surface to estimate all five parameters

Zero and low field nuclear magnetic resonance measurements have been performed on MAX phase samples (Cr 1− x Mn x ) 2 AC with A = Ge and Ga in order to obtain local microscopic information on the nature of magnetism in this system. Our results unambiguously provide evidence for the existence of long-range magnetic order in (Cr 0.96 Mn 0.04 ) 2 GeC and for (Cr 0.93 Mn 0.07 ) 2 GaC, but not for (Cr 0

We handshake statistical mechanics with continuum mechanics to develop a methodology for consistent evaluation of the continuum scale properties of two-dimensional materials. The methodology is tested on pristine graphene. Our scope is kept limited to elastic modulus, E , which has been reported to vary between 0.912 TPa and 7 TPa, Poisson’s ratio, ν , which has been reported to vary from being negative

The combination of two-dimensional crystals through the formation of van der Waals bilayers, trilayers, and heterostructures has been considered a promising route to design new materials due to the possibility of tuning their properties through the control of the number of layers, alloying pressure, strain, and other tuning mechanisms. Here, we report a density functional theory study on the interlayer

Using the constrained-path quantum Monte Carlo method, we systematically study the half-filled Hubbard model on AA-stacked honeycomb lattice. Our simulations demonstrate that a dominant chiral d + id wave superconductivity can be induced by a perpendicular electric field. At a fixed electric field, the effective pairing interaction of chiral d + id superconductivity exhibits an increasing behavior

Motivated by experimental results on transport properties of graphene covered by gallium atoms, the density functional theory study of clustering of gallium atoms on graphene (up to a size of 8 atoms) is presented. The paper explains a rapid initial increase of graphene electron doping by individual Ga atoms with Ga coverage, which is continually reduced to zero, when bigger multiple-atom clusters

An efficient description of the structures of liquids and, in particular, the structural changes that happen with liquids on supercooling remains to be a challenge. The systems composed of soft particles are especially interesting in this context because they often demonstrate non-trivial local orders that do not allow to introduce the concept of the nearest-neighbor shell. For this reason, the use

In the ongoing pursuit of inorganic compounds suitable for solid-state devices, transition metal chalcogenides have received heightened attention due to their physical and chemical properties. Recently, alkali-ion transition metal chalcogenides have been explored as promising candidates to be applied in optoelectronics, photovoltaics and energy storage devices. In this work, we present a theoretical

We explored the electronic and magnetic properties of the lanthanide double perovskite Dy 2 FeCoO 6 by combining magnetization, Raman and Mössbauer spectroscopy and neutron diffraction along with density functional theory (DFT) calculations. Our magnetization measurements revealed two magnetic phase transitions in Dy 2 FeCoO 6 . First, a paramagnetic to antiferromagnetic transition at T N = 248 K and

This paper presents the results of studies of a low-frequency vibration spectrum of PbCo 1/3 Nb 2/3 O 3 (PCN) relaxor ferroelectric crystal using the Brillouin and Raman light scattering in the temperature range from 80 to 750 K. The analysis of the temperature behaviour of the longitudinal acoustic phonon in Brillouin scattering spectra showed no anomalies in the vicinity of ‘diffuse phase transition’

The particle laden sessile drops when dried on solid surfaces under certain conditions leave a deposit pattern wherein all the particles are confined to a narrow region close to the edge of the deposit. Such patterns which often form when coffee drops dry are referred to as the coffee ring patterns or the coffee stains. Recent research points to the formation of intriguing patterns when colloidal particle

Scanning tunneling microscopy (STM) is an indispensable tool in detecting Majorana bound states (MBSs) in vortices of topological superconductors. By reducing the computational complexity via non-uniform grids, we systematically study the tunnel coupling as well as the temperature dependence of the differential conductance of MBSs in two dimensional devices. Numerical results show that the conductance

In many tetrahedral network-forming liquids, structural relaxation is anomalously accelerated by compression over relatively low pressure ranges. Here, for silica, we study this problem through comparative molecular dynamics simulations using two different models. Under compression, the network structures are compacted by slight tuning of the intertetrahedral bond angles while nearly preserving the

Zeeman effect induced by the magnetic field introduces a splitting between the two valleys at K + and K − points of the Brillouin zone in monolayer semiconducting transition metal dichalcogenides. In consequence, the photoluminescence signal exhibits a field dependent degree of circular polarization. We present a comprehensive study of this effect in the case of a trion in monolayer MoTe 2 , showing

We have studied the effects of Zn doping on the structural and electronic properties of epitaxial NdNiO 3 thin films grown on single-crystal LaAlO 3 (001) (LAO) substrates by pulsed laser deposition. The films are deposited in two sets, one with variation in Zn doping, and another with variation in thickness for undoped and 2% Zn doping. The experimental investigations show that Zn occupies Ni-site

The design of uranium-based thermoelectric (TE) materials presents a novel and intriguing strategy for directly converting nuclear heat into electrical power. Using high-level first-principles approach combined with accurate solution of Boltzmann transport equation, we demonstrate that a giant n-type power factor of 13.8 mW m −1 K −2 and a peak ZT value of 2.2 can be realized in the heavy-fermion UN

Time and history dependent magnetization has been observed in a wide variety of materials, which are collectively termed as the glassy magnetic systems. However, such systems showing similar non-equilibrium magnetic response can be microscopically very different and they can be distinguished by carefully looking into the details of the observed metastable magnetic behavior. Canonical spin glass (SG)

Non-equilibrium domain wall dynamics on a perpendicularly magnetized nanowire manipulated by the transverse magnetic field pulse are numerically investigated. We systematically observe the large displacements of the chiral domain wall and the domain wall tilting angles generated by Dzyaloshinskii–Moriya interaction during the competition between the precession torque and the magnetic damping process

Intermittent dynamics driven by internal stress imbalances in disordered systems is a fascinating yet poorly understood phenomenon. Here, we study it for a coarsening foam. By exploiting differential dynamic microscopy and particle tracking we determine the dynamical characteristics of the foam at different ages in reciprocal and direct space, respectively. At all wavevectors q investigated, the intermediate

Co 3 Sn 2 S 2 has generated a growing interest as a rare example of the highly uniaxial anisotropic kagomé ferromagnet showing a combination of frustrated-lattice magnetism and topology. Recently, via precise measurements of the magnetization and AC susceptibility we have found a low-field anomalous magnetic phase (A-phase) with very slow spin dynamics that appears just below the Curie temperature

We present a model equation of states for expanded metals, which contains a pressure term due to a screened-Coulomb potential with a screening parameter reflecting the Mott–Anderson metal-to-nonmetal transition. As anticipated almost 80 years ago by Zel’dovich and Landau, this term gives rise to a second coexistence line in the phase diagram, indicating a phase separation between a metallic and a nonmetallic

The Debye relaxation is the main signal in the dielectric measurements of monoalcohols arising from the hydrogen-bonded superstructures, but its physics remains to be cleared. In this work, a monoalcohol of 4-methyl-2-pentanol is studied using dielectric spectroscopies recorded at high pressures. The dynamic parameters of the Debye and structural relaxations are extracted. The calculation of the Kirkwood

The properties of dense hot hydrogen, in particular the phase transition between the molecular insulating and atomic conductive states, are important in the fields of astrophysics and high-pressure physics. Previous ab initio calculations suggested the metallization in liquid hydrogen, accompanied by dissociation, is a first-order phase transition and ends at a critical point in temperature range between

Helium ion beam interactions with materials have important implications for magnetic confinement fusion, material modification, and helium ion microscopy. These interactions depend on the precise physics of how helium ions channel into the materials, which can vary greatly based on the local crystalline orientation. In this work, we performed a dedicated experiment to investigate helium ion channeling

The theoretical investigation on structural, vibrational, and electronic properties of zinc-blende (ZB) AgI were carried out employing first principles density functional theory calculations. Thermoelectric properties then were predicted through semi-classical Boltzmann transport equations within the constant relaxation time approximation. Equilibrium lattice parameter, bulk modulus, elastic constants

In this work the role of magnetic Landau quantization in the dynamics and spectrum of diced lattice charge carriers is studied in terms of the associated pseudospin 1 Green’s function. The equations of motion for the 9 matrix elements of this Green’s function are formulated in position/frequency representation and are solved explicitly in terms of a closed form integral representation involving only

We show that topology is a very effective tool, to construct classical Hamiltonian time crystals. For this we numerically analyze a general class of time crystalline Hamiltonians that are designed to model the dynamics of molecular closed strings. We demonstrate how the time crystalline qualities of a closed string are greatly enhanced when the string becomes knotted. The Hamiltonians that we investigate

Using a recently developed approach to represent ab initio based force fields by a neural network potential, we perform molecular dynamics simulations of lead telluride and cadmium telluride crystals. In particular, we study the diffusion of a single cation interstitial in these two systems. Our simulations indicate that the interstitials migrate via two distinct mechanisms: through hops between interstitial

It is well known that the carrier-optical-phonon scattering rates dominate the carrier-acoustic-phonon scattering rates in many polar materials of interest in electronic and optoelectronic applications. Furthermore, it is known that the Fröhlich coupling constants for carrier-optical-phonon in many materials is close to or great than unity, calling into question the validity of scattering rates based

Hexagonal R MnO 3 ( R = Er, Ho and Yb) single crystals were grown and their unique vortex domain structures, magnetic properties and magnetocaloric effect (MCE) were comprehensively investigated. The topological vortex domains/structures were clearly illustrated by polarized optical microscope and piezo response force microscopy, confirming a high quality of the crystals. The magnetic transitions related

The excitation of magnetically ordered materials with ultrashort laser pulses results in magnetization dynamics on femto- to picosecond timescales. These non-equilibrium spin dynamics have emerged as a rapidly developing research field in recent years. Unraveling the fundamental microscopic processes in the interaction of ultrashort optical pulses with the charge, spin, orbital, and lattice degrees

We investigate the translocation dynamics of a folded linear polymer which is pulled through a nanopore by an external force. To this end, we generalize the iso-flux tension propagation theory for end-pulled polymer translocation to include the case of two segments of the folded polymer traversing simultaneously trough the pore. Our theory is extensively benchmarked with corresponding molecular dynamics

Chiral interfaces provide a new platform to execute quantum control of light-matter interactions. One phenomenon which has emerged from engineering such nanophotonic interfaces is spin-momentum locking akin to similar reports in electronic topological materials and phases. While there are reports of spin-momentum locking with combination of chiral emitters and/or chiral metamaterials with directional

Due to the strain gradient near each surface of a BaTiO 3 nanocube in their ordered assembly, electric polarization appears due to flexoelectric effect. The magnitude of the flexoelectric polarization could be one order of magnitude larger than that of ferroelectric spontaneous polarization of BaTiO 3 . Thus, dielectric response of an assembly could be dominated by that of the flexoelectric polarization

A new ternary uranium germanide U 2 Rh 3 Ge 5 has been successfully synthesized and investigated by means of magnetic susceptibility χ ( T , H ), isothermal magnetization M ( T , H ), electrical resistivity ρ ( T ), and specific heat C ( T , H ) measurements. This compound is found to crystallize in the U 2 Co 3 Si 5 -type orthorhombic structure. The low-field χ ( T ) shows a clear peak at T N = 41

Conformational effect on electronic localization is critically investigated for the first time considering a double-stranded helical geometry (DSHG) subjected to an electric field. In the presence of electric field the DSHG behaves like a correlated disordered system whose site potentials are modulated in a cosine form like the well known Aubry–André–Harper model. The potential distribution can be

We investigate, firstly, the competition between the Rashba spin–orbit coupling (SOC) and the intrinsic SOC in Kane–Mele model. For the small intrinsic SOC, we investigate the effects of the Rashba SOC on the touching point of the valence and conduction bands when the ratio of the Rashba SOC to the intrinsic SOC is greater than classical value ##IMG## [http://ej.iop.org/images/0953-8984/32/50/505601/cmabb517ieqn1

The structural, magnetic and dielectric properties have been investigated in 3 d –5 d based double perovskite Sr 2 FeIrO 6 thin films deposited by pulse laser deposition technique. To understand the effect of strain, epitaxial films are grown with varying thickness as well as on different substrates i.e., SrTiO 3 (100) and LaAlO 3 (100). The films with highest thickness are found to be more relaxed

The behaviour of stoichiometric U 1− y Pu y O 2 compounds used as nuclear fuel is relatively well understood. Conversely, the effects of stoichiometry deviation on fuel performance and fuel stability are intricate and poorly studied. In order to investigate what affect these have on the thermophysical properties of hypo-stoichiometric U 1− y Pu y O 2− x mixed oxide fuel, new interaction parameters

Antiferromagnetic materials can be the suitable functional elements for designing of future spin based electronic devices, circumventing the use of conventional ferromagnetic materials and spin–orbit coupled systems. In the present work first time we put forward the underlying physical mechanism, to the best of our knowledge, to generate polarized spin current through a magnetic material having zero

Chern insulators (CIs) or quantum anomalous Hall (QAH) states have drawn more attention, with emergence of quantized Hall conductance but in absence of Landau levels. Here, we study the Haldane-type CI/QAH states on Möbius strips and focus on the quantum transport properties. The Möbius strips can be constructed from the twisted honeycomb-lattice strips with domain walls. Topological properties of

The stoichiometric Ni 50 Mn 25 In 25 Heusler alloy transforms from a stable ferromagnetic austenitic ground state to an incommensurate modulated martensitic ground state with a progressive replacement of In with Mn without any pre-transition phases. The absence of pre-transition phases like strain glass in Ni 50 Mn 25+ x In 25− x alloys is explained to be the ability of the ferromagnetic cubic structure

We report detailed temperature-dependent inelastic neutron scattering and ab initio lattice dynamics investigation of magnetic perovskites YCrO 3 and LaCrO 3 . The magnetic neutron scattering from the Cr ions exhibits significant changes with temperature and dominates at low momentum transfer regime. Ab initio calculations performed including magnetic interactions show that the effect of magnetic interactions

We investigate the ground-state and dynamical properties of nonuniform two-dimensional (2D) clusters of long-range interacting particles. We demonstrate that, when the confining external potential is designed to produce an approximate 1/ r 2 density profile, the particles crystallize into highly ordered structures featuring spiral crystalline lines. Despite the strong inhomogeneity of the observed

Thin films of Bi (1− x ) Sr x FeO 3 ( X = 0.00, 0.05, 0.10, 0.20, and 0.30) are synthesized on ultra-cleaned glass substrates by simple spray pyrolysis method at 550 °C. The crystal structures of the thin films are investigated by x-ray diffraction (XRD). The Rietveld refinement data for all the thin films are confirmed a single-phase ABO 3 type of rhombohedral structure belonging to the R 3 c space

This work presents an analysis of the functional derivative of the superconducting transition temperature T c with respect to the electron-phonon coupling function α 2 F ( ω ) [ δT c / δα 2 F ( ω )] and α 2 F ( ω ) spectrum of H 3 S ( ##IMG## [http://ej.iop.org/images/0953-8984/32/50/505901/cmabb741ieqn1.gif] {$\mathrm{Im}\bar{3}m$} ), in the pressure range where the high- T c was measured (155–225

The intrinsic magnetic low-frequency noise (LFN) is of fundamental scientific interest to the study of magnetic tunnel junctions (MTJs). To gain insight into its mechanism, the fluctuation-dissipation theorem, which describes the linear relation between magnetic LFN and magnetic sensitivity product, has been utilized. However, deviation from the linear correlation has been reported in some studies

A method of forming time-reversed low-energy electron diffraction (LEED) states using results of repeated-slab calculations is presented. The time-reversed LEED states are used in calculations of the matrix elements of photoelectron spectroscopy. The method is applied to spin- and angle-resolved photoelectron spectroscopy of the Bi(111) surface. Calculations are performed for excitation from surface

Hydrogenation and fluorination have been presented as two possible methods to open a bandgap in graphene, required for field-effect transistor applications. In this work, we present a detailed study of the phonon-limited mobility of electrons and holes in hydrogenated graphene (graphane) and fluorinated graphene (graphene fluoride). We pay special attention to the out-of-plane acoustic (ZA) phonons

The evolution of electrical resistance as function of defect concentration is examined for the unipolar n -conducting oxides CdO, β -Ga 2 O 3 , In 2 O 3 , SnO 2 and ZnO in order to explore the predictions of the amphoteric defect model. Intrinsic defects are introduced by ion irradiation at cryogenic temperatures, and the resistance is measured in-situ by current–voltage sweeps as a function of irradiation

We observe Andreev reflection in a YBCO–GaN junction through differential conductance spectroscopy. A strong characteristic zero-bias peak was observed and persisted up to the critical temperature of the superconductor with a smaller superconducting order parameter Δ ∼ 1 meV. The presence of Andreev reflection with the small Δ in comparison to its value for high- T c superconductors forms an important

We consider the three-dimensional Hamiltonian for Bi 2 Se 3 , a second-generation topological insulator, under the effect of a periodic drive for both in-plane and out-of-plane fields. As it will be shown by means of high-frequency expansions up to second order in the Floquet Hamiltonian, the driving induces anisotropies in the Dirac cone and opens up a quasienergy gap for in-plane elliptically polarized

Polycrystalline Nd 2 CoIrO 6 double perovskite crystallizes in monoclinic crystal structure with P 2 1 / n space group. The average grain size of powder sample is 400–500 nm. The dielectric, impedance and ac conductivity of the sample were studied in the temperature range 5–300 K and in the frequency range 20 Hz–2 MHz. Dielectric constant reveals a step like increase from low temperature value of ∼5

The magnetocrystalline anisotropy of GdRh 2 Si 2 is examined in detail via the electron spin resonance (ESR) of its well-localised Gd 3+ moments. Below T N = 107 K, long range magnetic order sets in with ferromagnetic layers in the ( aa )-plane stacked antiferromagnetically along the c -axis of the tetragonal structure. Interestingly, the easy-plane anisotropy allows for the observation of antiferromagnetic

A polycrystalline sample of Sr 2 ScFeAsO 3 was studied by 57 Fe Mössbauer spectroscopy down to 1.7 K. In contrast to the earlier Mössbauer data, the obtained in this work results indicate that Sr 2 ScFeAsO 3 is in paramagnetic state down to 10 K, while the spectra recorded at 4.6 K and 1.7 K show a weak magnetic order of Fe moments in the Fe 2 As 2 layers. Temperature dependences of isomer shift and

Computer simulation shows that an increase of the volume V due to point defects in a simple metallic crystal (Al) and high entropy alloy (Fe 20 Ni 20 Cr 20 Co 20 Cu 20 ) leads to a linear decrease of the shear modulus G . This diaelastic effect can be characterized by a single dimensionless parameter K = dln G /dln V . For dumbbell interstitials in single crystals K ≈ −30 while for vacancies the absolute

Based on first-principles calculations, the binding energy of hydrogen atom to Y 2 O 3 and Y 2 O 3 |bcc Fe interface (relative to bcc Fe side) with cube-on-cube orientation is at least 0.45 eV, if hydrogen substitutional is considered, or at least 0.26 eV if only hydrogen interstitial is considered. The calculated binding energies do not have a unique fixed value, because they are dependent on the

The role of finite size effects on magnetic order has been investigated in samarium nanoparticles prepared by physical vapor deposition. A dense layer composed of distinct nanoparticles with a mean particle diameter of 26 nm was deposited on a diamagnetic substrate. M ( T ) measurements identify the expected pair of antiferromagnetic ordering temperatures in the bulk Sm precursor, at 113 K and 14 K

In this work a comparison of dielectric and mechanical data is presented based on experiments within the linear response limit and beyond that limit. The linear dynamic and shear-mechanical response is discussed in terms of the molecular supercooled liquid tetramethyl-tetraphenyl-trisiloxane. As the dynamics measured by the two methods depict the same temperature-dependence, the underlying cause for

The perpendicular magnetic anisotropy (PMA) and the interfacial Dzyaloshinskii–Moriya interaction (iDMI) are investigated in as grown and 300 °C annealed Co-based ultrathin systems. For this, Co films of various thicknesses (0.8 nm ⩽ t Co ⩽ 5.7 nm) were deposited by magnetron sputtering on thermally oxidized Si substrates using Pt, W, Ir, Ti, Ru and MgO buffer or/and capping layers. X-ray diffraction