Structural phase transitions in f-electron materials have attracted sustained attention both for practical and basic science reasons, including that they offer an environment to directly investigate relationships between structure and the f-state. Here we present results for UCr2Si2, where structural (tetragonal → monoclinic) and antiferromagnetic phase transitions are seen at $T_{\rm{S}}$ = 205 K

A new hyperkagome iridate Li3Ir3O8 is synthesized by an ion-exchange reaction from Na4Ir3O8. The transport, magnetic and thermodynamic measurements suggest a metallic state}. The electronic structure calculation shows that Li3Ir3O8 hosts a semimetallic electronic structure} produced by a competition between the formation of a localized molecular orbital of Ir d-electrons on the Ir3 triangles and the

The incorporation of indium in GaN (0001) surfaces in dependence of strain is investigated by combining molecular beam epitaxy (MBE) growth, quantitative transmission electron microscopy and density functional theory (DFT) calculations. Growth experiments were conducted on GaN, as well as on 30 layers, coherently overgrown by GaN. Despite the only 0.6 in-plane lattice constant of GaN provided by the

We investigated the Dirac-cone state and its modulation when an ultrathin film of topological insulator Bi2Se3 was epitaxially grown on a van-der-Waals ferromagnet Cr2Si2Te6 (CST) by angle-resolved photoemission spectroscopy. We observed a gapless Dirac-cone surface state in 6 quintuple-layer (QL) Bi2Se3 on CST, whereas the Dirac cone exhibits a gap of 0.37 eV in 2QL counterpart. Intriguingly, this

The formation of an ultra-thin aluminum oxide film at the Fe0.85Al0.15(110) surface (A2 random alloy) has been studied by a variety of surface sensitive techniques (X-ray photoemission, low-energy electron diffraction, surface X-ray diffraction and scanning tunneling microscopy) supplemented by {} atomistic simulations. Since iron is not oxidized in the conditions used, the study focused on the coupling

Enhancing the electromechanical response by engineering domain boundaries in multiferroics has become a highly active research field in recent years. The starting point is the discovery that ferroelastic twin walls are polar inside a non-polar matrix. The density of such twin walls is then greatly enhanced by forming complex twin patterns. Our computer simulations show that the interaction of nano-cavities

While it is known that alloy components can segregate to grain boundaries (GBs), and that the atomic mobility in GBs greatly exceeds the atomic mobility in the lattice, little is known about the effect of GB segregation on GB diffusion. Atomistic computer simulations offer a means of gaining insights into the segregation-diffusion relationship by computing the GB diffusion coefficients of the alloy

Graphene functionalization by hydrogen and fluorine has been proposed as a route to modulate its reactivity and electronic properties. However, until now, proposed systems present degradation and limited hydrogen adsorption capacity. In this study, combining first-principles calculations based on density functional theory (DFT) and reactive molecular dynamics, we analyze the tuning of hydrogen adsorption

The incorporation of point defects into semiconductors could substantially tailor their optical and electrical properties, as well as the spin-based quantum properties. In terms of structural properties, however, efforts have seldom been devoted to the relevant aspects. Herein, we propose a point defects engineering by intentionally introduced vacancies to improve the structural properties. GaN-on-Si

We show that when TiO2 anatase (001) is exposed to hydrogen plasma that the pristine surface termination becomes unfavorable to another, slightly modified, surface. On this modified surface the topmost TiO2 layer is intact, but out of registry with the bottom layers. Nevertheless, the modified surface has significantly improved ability to split water under exposure to sunlight. We show by explicit

The electronic, and magnetic properties of the magnetoelectric solid GaFeO3 are investigated within the generalized gradient approximation including the Hubbard interaction (U) on the localized d orbitals of iron. It was found that using an on-site U=8 eV describes consistently the experimental results. The origin of ferrimagnetism was attributed to the cationic site disorders. The density of states

We report epitaxial growth of vanadium diselenide (VSe2) thin films in the octahedrally-coordinated (1T) structure on GaAs(111)B substrates by molecular beam epitaxy. Film thickness from a single monolayer (ML) up to 30 ML is demonstrated. Structural and chemical studies using by x-ray diffraction, transmission electron microscopy, scanning tunneling microscopy and x-ray photoelectron spectroscopy

The transition temperature (Tc) between normal and superconducting states usually exhibits a dramatic increase or decrease with increasing applied pressure. Here we present, in contrast, a new kind of superconductor that exhibits the exotic feature that Tc is robust against large volume shrinkages induced by applied pressure (here naming them as “RSAVS superconductors”). Extraordinarily, the Tc in

We present an interacting model for the electronic and magnetic behavior of a strained (001) atomic layer of Sr2FeMoO6, which shows room-temperature ferrimagnetism and magnetoresistance with potential spintronics application in the bulk. We find that the strong spin-orbit coupling in the molybdenum 4d shell gives rise to a robust ferrimagnetic state with an emergent spin-polarized electronic structure

Lead halide perovskites have emerged as new optoelectronic materials owing to the outstanding optical properties. There has been increased interest in their temperature-sensitive optical properties and new optical applications have been proposed thereby. Here, we report the origin of the unusual negative thermo-optic coefficient of the halide perovskite CH3NH3PbCl3, i.e., a decrease in the refractive

We theoretically investigate the application of topological plasmon polaritons (TPPs) to achieving robust temperature sensing. Based on an analogy of the topological edge states in the Su-Schrieffer-Heeger model, TPPs are realized in a one-dimensional intrinsic indium antimonide (InSb) microsphere chain. The existence of TPPs is demonstrated by analyzing the topology of the photonic band structures

A steady-state photocapacitance (SSPC) setup directly connected to the beam line of a MeV ion implanter is utilized to study primary intrinsic defects in β-Ga2O3 generated by He implantation at cryogenic temperatures (). At low temperatures, the migration of defects is suppressed, and hence the generation of primary intrinsic defects is expected to prevail. SSPC measurements reveal defect-related optical

Extended planar defects found in epitaxially grown SrFeO3-thin films are expected to exhibit distinct conductivity properties. Here, we use a combination of scanning transmission electron microscopy techniques and electron energy-loss spectroscopy (EELS) to uncover the peculiar structure of these planar defects and to explore their electronic properties. We find that the defects are formed by Fe2O2+

α−Al2O3 is widely used for high-temperature structural materials in the form of polycrystals, and the physical and chemical properties are significantly influenced by the impurity types and their concentrations. Although the concentrations of some impurities in α−Al2O3 have been experimentally investigated, there are no detailed reports on the point-defect structures and their charge states. In this

Transition metal dichalcogenide (TMD) materials have received enormous attention due to their extraordinary optical and electrical properties, among which MoS2 is the most typical one. As the thickness increases from monolayer to multilayer, the photoluminescence (PL) of MoS2 is gradually quenched due to the direct-to-indirect band gap transition. How to enhance PL response and decrease the layer dependence

La0.4Ce0.6Co2P2 represents a borderline case in the range of solid solutions formed in the pseudo-binary system LaCo2P2-CeCo2P2. The material undergoes ferromagnetic ordering at ~225 K followed by a structural collapse at ~190 K, which leads to a strong suppression of magnetization. The structural phase transition manifests itself in a gradual decrease in the parameter c and a relatively smaller in-crease

Deformation twinning is one of the major deformation mechanisms in crystals, which plays an important role in determining the mechanical properties of metals and alloys. One of the important issues to understand twinning mechanisms is the determination of deformation path. However, due to a lack of theoretical tools, a fundamental relationship between symmetry breaking and deformation path has not

Tilt {112} grain boundaries (GBs) in bcc metals perform shear-coupled grain boundary migration by the creation and glide of disconnections. Disconnection dipoles may be created at the pristine GB at high stresses or may be generated at the core of a GB dislocation that acts as a source of disconnections. We characterize this source in terms of its Burgers vector, denoted b⃗1/−1, and describe the mechanism

A suspended layer made up of ferromagnetically ordered spins could be created between two mono/multilayer graphene through intercalation. Stability and electronic structure studies show that, when fluorine molecules are intercalated between two mono/multilayer graphene, their bonds get stretched enough (∼ 1.9$-$2.0 ) to weaken their molecular singlet eigenstate. Geometrically, these stretched molecules

Hybrid improper ferroelectricity (HIF) is recognized as a promising way to design room temperature multiferroic materials with strong magnetoelectric coupling. However, predicting new HIF materials with high ferroelectric polarization remains to be a great challenge. Here, the new compound Ba3Ce2O7 with Ruddlesden-Popper (R-P) structure, which crystallizes in polar A21am phase has been proposed and

The magnetic order and the spin dynamics in the antiferromagnetic entropy-stabilized oxide (Mg0.2Co0.2Ni0.2Cu0.2Zn0.2)O (MgO-ESO) have been studied using muon spin relaxation () and inelastic neutron scattering. We find that antiferromagnetic order develops gradually in the sample volume as it is cooled below 140 K, becoming fully ordered around 100 K. The spin dynamics show a critical slowing down