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Nature of the magnetic moment of cobalt in ordered FeCo alloy J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-16 Arsenii Gerasimov, Lars Nordstrm, Sergii Khmelevskyi, Vladimir V Mazurenko, Yaroslav O Kvashnin
The magnets are typically classified into Stoner and Heisenberg type, depending on the itinerant or localized nature of the constituent magnetic moments. In this work, we investigate theoretically the behaviour of the magnetic moments of iron and cobalt in their B2-ordered alloy. The results based on local spin density approximation for the density functional theory (DFT) suggest that the Co magnetic
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Anisotropic magnetotransport in tilted magnetic topological semimetals J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-16 J Wu, C M Wang
We systematically investigate the anisotropic magneto-conductivity and planar Hall effect in tilted magnetic topological semimetals in the frame of Kubo formula by considering the vertex correction of velocity. The nonzero anisotropic magneto-conductivity is due to the intrinsic magnetization by magnetic doping rather than the external magnetic field previously studied in literatures. In the scenario
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Soft mode theory of ferroelectric phase transitions in the low-temperature phase J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-16 Luigi Casella, Alessio Zaccone
Historically, the soft mode theory of ferroelectric phase transitions has been developed for the high-temperature (paraelectric) phase, where the phonon mode softens upon decreasing the temperature. In the low-temperature ferroelectric phase, a similar phonon softening occurs, also leading to a bosonic condensation of the frozen-in mode at the transition, but in this case the phonon softening occurs
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The drag of photons by electric current in quantum wells J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-16 G V Budkin, I S Makhov, D A Firsov
The flow of electric current in quantum well breaks the space inversion symmetry, which leads to the dependence of the radiation transmission on the relative orientation of current and photon wave vector, this phenomenon can be named current drag of photons. We have developed a microscopic theory of such an effect for intersubband transitions in quantum wells taking into account both depolarization
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High temperature stability, metallic character and bonding of the Si2BN planar structure J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-16 Zacharias G Fthenakis, Meghnath Jaishi, Badri Narayanan, Antonis N Andriotis, Madhu Menon
The family of monolayered Si2BN structures constitute a new class of 2D materials exhibiting metallic character with remarkable stability. Topologically, these structures are very similar to graphene, forming a slightly distorted honeycomb lattice generated by a union of two basic motifs with AA and AB stacking. In the present work we study in detail the structural and electronic properties of these
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Impact of noble-gas filler atoms on the lattice thermal conductivity of CoSb3 skutterudites: first-principles modelling J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-16 Jianqin Tang, Jonathan M Skelton
We present a systematic first-principles modelling study of the structural dynamics and thermal transport in CoSb3 skutterudites with a series of noble-gas filler atoms. Filling with chemically-inert atoms provides an idealised model for isolating the effects of the fillers from the impact of redox changes to the host electronic structure. A range of analysis techniques are proposed to estimate the
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A NIST facility for resonant soft x-ray scattering measuring nano-scale soft matter structure at NSLS-II J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-16 Eliot Gann, Thomas Crofts, Glenn Holland, Peter Beaucage, Terry McAfee, R Joseph Kline, Brian A Collins, Christopher R McNeill, Daniel A Fischer, Dean M DeLongchamp
We present the design and performance of a polarized resonant soft x-ray scattering (RSoXS) station for soft matter characterization built by the national institute of standards and technology at the national synchrotron light source-II (NSLS-II). The RSoXS station is located within the spectroscopy soft and tender beamline suite at NSLS-II located in Brookhaven national laboratory, New York. Numerous
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High energy surface x-ray diffraction applied to model catalyst surfaces at work J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-10 Uta Hejral, Mikhail Shipilin, Johan Gustafson, Andreas Stierle, Edvin Lundgren
Catalysts are materials that accelerate the rate of a desired chemical reaction. As such, they constitute an integral part in many applications ranging from the production of fine chemicals in chemical industry to exhaust gas treatment in vehicles. Accordingly, it is of utmost economic interest to improve catalyst efficiency and performance, which requires an understanding of the interplay between
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Metastable solid 4He and the possible role of point defects J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 V Z Pedroso, V Zampronio, S A Vitiello
The metastable phase of solid 4He and the possible role of point defects in its destabilization are investigated by the introduction of a trial function of the shadow class with an explicit symmetrical kernel. This is a trial function that ensures the possible exchange of atoms and the delocalization of atoms and defects in a very effective manner. We show that the formation energy for vacancies is
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Electron beam triggered single-atom dynamics in two-dimensional materials J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Xiaoxu Zhao, Kian Ping Loh, Stephen J Pennycook
Controlling atomic structure and dynamics with single-atom precision is the ultimate goal in nanoscience and nanotechnology. Despite great successes being achieved by scanning tunneling microscopy (STM) over the past a few decades, fundamental limitations, such as ultralow temperature, and low throughput, significantly hinder the fabrication of a large array of atomically defined structures by STM
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Spin reorientation behaviour and dielectric properties of Fe-doped h-HoMnO3 J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Pulkit Prakash, S K Mishra, C L Prajapat, A Das
We have studied the magnetic structure, spin reorientation behaviour and dielectric properties of polycrystalline HoMn1−x Fe x O3 (0.0 ⩽ x ⩽ 0.25) compounds using magnetization, neutron diffraction and dielectric measurements. These compounds crystallize predominantly in the hexagonal phase (P63 cm) with a small phase fraction of the orthorhombic phase (Pnma) which increases with increase in dopant
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Hysteresis in centrosymmetric CuPbI3 perovskite halide: apolar dielectric or orientable dielectric? J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Prem C Bharti, Pardeep K Jha, Priyanka A Jha, Prabhakar Singh
We demonstrated the change in polarization behaviour at the surface/interface before and after light through Havriliak–Negami equation of lesser known CuPbI3. We have synthesized CuPbI3 through cold sintering technique and the polarization mechanisms are altered by increasing (cold) sintering temperature. The structure of CuPbI3 was not known and we predicted it to be hexagonal (Rm) with 21R prototype
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Multi-orbital tight binding model for the electronic and optical properties of armchair graphene nanoribbons in the presence of a periodic potential J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Nguyen N Hieu, Po-Hsin Shih, Thi-Nga Do, Chuong V Nguyen
The influences of an external electric field with uniform or modulated potential on the electronic and optical properties of armchair graphene nanoribbons (GNRs) are explored using the multi-orbital tight-binding Hamiltonian. The interplay between an electric field and interaction between (s, p x , p y , p z ) orbitals remarkably enriches the main features of band structures and absorption spectra
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The thermodynamic stability and mechanical properties of TiC x N1−x (0 ⩽ x ⩽ 1) compounds by cluster expansion method and first-principles calculations J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Yijie Chen, Canhui Xu, Shuanglin Hu, Xiaojun Zhao, Lairong Xiao, Zhenyang Cai
The thermodynamic stability and mechanical properties of titanium carbonitrides TiC x N1−x (0 ⩽ x ⩽ 1) are investigated by a combination of the universal cluster expansion method and the first-principles calculations. By considering the ordering of the N/C distributions on the anion sublattice sites of TiC x N1−x , a binary diagram of the heat of formation is constructed, and seven kinds of ground-state
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Exploring structural, electronic, and mechanical properties of 2D hexagonal MBenes J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Rasoul Khaledialidusti, Mohammad Khazaei, Vei Wang, Nanxi Miao, Chen Si, Jianfeng Wang, Junjie Wang
A family of two-dimensional (2D) transition metal borides, referred to as MBenes, is recently emerging as novel materials with great potentials in electronic and energy harvesting applications to the field of materials science and technology. Transition metal borides can be synthesized from chemical exfoliation of ternary-layered transition metal borides, known as MAB phases. Previously it has been
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Exchange interactions in ɛ-Fe2O3: GGA + U calculations J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 K Knžek, P Novk, Z Jirk
We have studied the origin of magnetic interaction in ɛ-Fe2O3 by ab-initio electronic structure calculations. The exchange integrals of the Heisenberg Hamiltonian have been calculated using the methods based on the density functional theory (DFT) employing generalized gradient approximation (GGA) with orbital dependent potential extension for 3d electrons of Fe (GGA + U method). The calculations confirm
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Growth, electronic structure and superconductivity of ultrathin epitaxial CoSi2 films J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Yuan Fang, Ding Wang, Peng Li, Hang Su, Tian Le, Yi Wu, Guo-Wei Yang, Hua-Li Zhang, Zhi-Guang Xiao, Yan-Qiu Sun, Si-Yuan Hong, Yan-Wu Xie, Huan-Hua Wang, Chao Cao, Xin Lu, Hui-Qiu Yuan, Yang Liu
We report growth, electronic structure and superconductivity of ultrathin epitaxial CoSi2 films on Si (111). At low coverages, preferred islands with 2, 5 and 6 monolayers height develop, which agrees well with the surface energy calculation. We observe clear quantum well states as a result of electronic confinement and their dispersion agrees well with density functional theory calculations, indicating
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Emergence of −s, −p–d band inversion in zincblende gold iodide topological insulator and its thermoelectric properties J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Raghottam M Sattigeri, Trupti K Gajaria, Prafulla K Jha, Piotr Śpiewak, Krzysztof J Kurzydłowski
We employ first-principles calculations to investigate the topological states (TS) and thermoelectric (TE) transport properties of three dimensional (3D) gold iodide (AuI) which belongs to the zincblende family. We explore, semi-metal (SM) to topological conductor (TC) and topological insulator (TI) phase transitions. Under pristine conditions, AuI exhibits Dirac SM nature but, under the influence
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Excitations of atomic vibrations in amorphous solids J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Li Wan
We study excitations of atomic vibrations in the reciprocal space for amorphous solids. There are two kinds of excitations we obtained, collective excitation and local excitation. The collective excitation is the collective vibration of atoms in the amorphous solids while the local excitation is stimulated locally by a single atom vibrating in the solids. We introduce a continuous wave vector for the
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Direct band gap and strong Rashba effect in van der Waals heterostructures of InSe and Sb single layers J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Dangqi Fang, Siyu Chen, Yaqi Li, Bartomeu Monserrat
Van der Waals heterostructures formed by stacking different types of 2D materials are attracting increasing attention due to new emergent physical properties such as interlayer excitons. Recently synthesized atomically thin indium selenide (InSe) and antimony (Sb) individually exhibit interesting electronic properties such as high electron mobility in the former and high hole mobility in the latter
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Stress effect on segregation and ordering in Pt–Ag nanoalloys J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Alexis Front, Christine Mottet
We performed a theoretical study of the chemical ordering and surface segregation of Pt–Ag nanoalloys in the range of size from 976 to 9879 atoms (3.12 to 6.76nm). We used an original many-body potential able to stabilize the L11 ordered phase at equiconcentration leading to a strong silver surface segregation. Based on a recent experimental study where nanoparticles up to 2.5nm have been characterized
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The nuts and bolts of core-hole constrained ab initio simulation for K-shell x-ray photoemission and absorption spectra J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Benedikt P Klein, Samuel J Hall, Reinhard J Maurer
X-ray photoemission (XPS) and near edge x-ray absorption fine structure (NEXAFS) spectroscopy play an important role in investigating the structure and electronic structure of materials and surfaces. Ab initio simulations provide crucial support for the interpretation of complex spectra containing overlapping signatures. Approximate core-hole simulation methods based on density functional theory (DFT)
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Investigating the energetic and entropic components of effective potentials across a glass transition J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Ryan J Szukalo, W G Noid
By eliminating unnecessary details, coarse-grained (CG) models provide the necessary efficiency for simulating scales that are inaccessible to higher resolution models. However, because they average over atomic details, the effective potentials governing CG degrees of freedom necessarily incorporate significant entropic contributions, which limit their transferability and complicate the treatment of
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Effect of Pd alloying on structural, electronic and magnetic properties of L10 Fe–Ni J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Prashant Singh, Debashish Das, Duane D Johnson, Raymundo Arroyave, Aftab Alam
We present a systematic study of the effect of Pd-alloying on phase stability, electronic structure, and elastic properties in L10 Fe–Ni using density-functional theory. Being from the same group of the periodic table, Pd is the best candidate for chemical alloying. The Fe–Ni/Fe–Pd/Ni–Pd bond-length increases with increasing Pd-concentration, which weakens the hybridization between low lying energy
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Self-diffusion of nonspherical particles fundamentally conflicts with effective sphere models J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Felix Roosen-Runge, Peter Schurtenberger, Anna Stradner
Modeling diffusion of nonspherical particles presents an unsolved and considerable challenge, despite its importance for the understanding of crowding effects in biology, food technology and formulation science. A common approach in experiment and simulation is to map nonspherical objects on effective spheres to subsequently use the established predictions for spheres to approximate phenomena for nonspherical
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The phase diagram of Ti-6Al-4V at high-pressures and high-temperatures J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 S G MacLeod, D Errandonea, G A Cox, H Cynn, D Daisenberger, S E Finnegan, M I McMahon, K A Munro, C Popescu, C V Storm
We report results from a series of diamond-anvil-cell synchrotron x-ray diffraction and large-volume-press experiments, and calculations, to investigate the phase diagram of commercial polycrystalline high-strength Ti-6Al-4V alloy in pressure–temperature space. Up to ∼30GPa and 886K, Ti-6Al-4V is found to be stable in the hexagonal-close-packed, or α phase. The effect of temperature on the volume expansion
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Transition-metal adatoms on 2D-GaAs: a route to chiral magnetic 2D materials by design J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 A Gonzlez-Garca, W Lpez-Prez, R Gonzlez-Hernndez, C Bacaksiz, D Šabani, M V Milošević, F M Peeters
Using relativistic density-functional calculations, we examine the magneto-crystalline anisotropy and exchange properties of transition-metal atoms adsorbed on 2D-GaAs. We show that single Mn and Mo atom (Co and Os) strongly bind on 2D-GaAs, and induce local out-of-plane (in-plane) magnetic anisotropy. When a pair of TM atoms is adsorbed on 2D-GaAs in a close range from each other, magnetisation properties
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Quantum defect-assisted multiphonon Raman scattering in metal halide perovskites J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Zi-Wu Wang, Yong Sun, Yu Cui, Yao Xiao, Jia-Pei Deng, Wen Xiong, Zhi-Qing Li
Quantum defects are essential to understand the non-radiative recombination processes in metal halide perovskites-based photovoltaic devices, in which Huang–Rhys factor, reflecting the coupling strength between the charge carrier and optical phonons, plays a key role in determining the non-radiative recombination via multiphonon processes. Herein, we theoretically present multiphonon Raman scattering
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Floquet–Dirac fermions in monolayer graphene by Wannier functions J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Jian Liu, Wenjie Hou, Lei Sun, Xikui Ma, Xukun Feng, Tianxiao Nie, Mingwen Zhao
Wannier functions have been widely applied in the study of topological properties and Floquet–Bloch bands of materials. Usually, the real-space Wannier functions are linked to the k-space Hamiltonian by two types of Fourier transform (FT), namely lattice-gauge FT (LGFT) and atomic-gauge FT (AGFT), but the differences between these two FTs on Floquet–Bloch bands have rarely been addressed. Taking monolayer
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Exact solution to sodium-iridate-BCS– Hubbard model along the symmetric line: non-trivial topology in the ferromagnetic order J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Shihao Bi, Yan He, Peng Li
We study the sodium-iridates model on the honeycomb lattice with both BCS pairing potential and Hubbard interaction term. It is shown that this model can be exactly solved with appropriate choices of amplitude of pairing gaps, where the interacting terms are transformed to external field terms. The band structures of these exact solutions on both torus and cylinder geometry are discussed in great details
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Ab initio study of electronic and magnetic properties of Mn2RuZ/MgO (001) heterojunctions (Z = Al, Ge) J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Tufan Roy, Masahito Tsujikawa, Masafumi Shirai
We studied the applicability of Heusler alloys Mn2RuZ (Z = Al, Ga, Ge, Si) to the electrode materials of MgO-based magnetic tunnel junctions. All these alloys possess Hg2CuTi-type inverse Heusler alloy structure and ferrimagnetic ground state. Our study reveals the half-metallic electronic structure with highly spin-polarized Δ1 band, which is robust against atomic disorder. Next we studied the electronic
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Tailoring the electronic structure and magnetic properties of pyrochlore Co2Ti1−x Ge x O4: a GGA + U ab initio study J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Sayandeep Ghosh, Sobhit Singh, Debashish Das, Subhradip Ghosh, Pankaj Kumar Mishra, Subhash Thota
We report the electronic structure and magnetic properties of Co2Ti1−x Ge x O4 (0 ⩽ x ⩽ 1) spinel by means of the first-principle methods of density functional theory involving generalized gradient approximation along with the on-site Coulomb interaction (U eff) in the exchange-correlation energy functional. Special emphasis has been given to explore the site occupancy of Ge atoms in the spinel lattice
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A new prescription to achieve a high degree of spin polarization in a spin–orbit coupled quantum ring: efficient engineering by irradiation J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Sudin Ganguly, Santanu K Maiti
The present work discusses the possibility to achieve a high degree of spin polarization in a three-terminal quantum system. Irradiating the system, subjected to Rashba spin–orbit (SO) interaction, we find high degree of spin polarization under a suitable input condition along with different magnitudes and phases at the two output leads. The system is described within a tight-binding (TB) framework
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Effect of logarithmic perturbations in ohmic like spectral densities in dynamics of electronic excitation using variational polaron transformation approach J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 Nisal De Silva, Tharindu Warnakula, Sarath D Gunapala, Mark I Stockman, Malin Premaratne
Electronic excitation energy transfer is a ubiquitous process that has generated prime research interest since its discovery. Recently developed variational polaron transformation-based second-order master equation is capable of interpolating between Frster and Redfield limits with exceptional accuracy. Forms of spectral density functions studied so far through the variational approach provide theoretical
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Spin polarization in lateral two-dimensional heterostructures J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-03-08 S Hannan Mouasvi, H Simchi
In this work, we study the spin polarization in the MoS(Se)2–WS(Se)2 transition metal dichalcogenide heterostructures by using the non-equilibrium Green’s function method and a three-band tight-binding model near the edges of the first Brillouin zone. Although it has been shown that the structures have no significant spin polarization in a specific range of energy of electrons, by applying a transverse
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Thermal conductivity of h-BN monolayers using machine learning interatomic potential J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Yixuan Zhang, Chen Shen, Teng Long, Hongbin Zhang
Thermal management materials are of critical importance for engineering miniaturized electronic devices, where theoretical design of such materials demands the evaluation of thermal conductivities which are numerically expensive. In this work, we applied the recently developed machine learning interatomic potential (MLIP) to evaluate the thermal conductivity of hexagonal boron nitride monolayers. The
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Controlling soft vortex matter: edge effects on vortex configurations and partial vortices in a superconducting type-II/type-I bilayer J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 W Y Crdoba-Camacho, R M da Silva, J Barba-Ortega, J Albino Aguiar
We demonstrate that the presence of edges in a superconducting film made of a type-I/type-II bilayer stabilizes type-II/type-I hybrid (inter-type) flux patterns, as vortex clusters, chains, and gel phase. These patterns are very sensitive to primary parameters such as applied magnetic field, layer coupling, and temperature. Thus, the magnetization versus temperature curves, M(T), for many values of
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Powder diffraction computed tomography: a combined synchrotron and neutron study J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Vladislav Kochetov, Martin J Mhlbauer, Alexander Schkel, Torben Fischer, Timo Mller, Michael Hofmann, Peter Staron, Ulrich Lienert, Winfried Petry, Anatoliy Senyshyn
Diffraction and imaging using x-rays and neutrons are widely utilized in different fields of engineering, biology, chemistry and/or materials science. The additional information gained from the diffraction signal by x-ray diffraction and computed tomography (XRD-CT) can give this method a distinct advantage in materials science applications compared to classical tomography. Its active development over
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Intrinsic ferromagnetic semiconductors in rhombohedral RMnO3 (R = Sc, Y, and Lu) with high critical temperature and large ferroelectric polarization J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Chengfeng Zhang, Zixu Li, Guannan Li, Benling Gao, Feng Liang, Zhongwen Li, Guang Song
Ferromagnetic (FM) semiconductors have been recognized as the cornerstone for next-generation highly functional spintronic devices. However, the development in practical applications of FM semiconductors is limited by their low Curie temperatures (T C). Here, on the basis of model analysis, we find that the FM super-exchange couplings in the d 5 − d 3 system can be significantly strengthened by reducing
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Magnus-force induced skyrmion–antiskyrmion coupling in inhomogeneous racetrack J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 R C Silva, R L Silva, A R Pereira
In this paper we investigate a magnetic racetrack consisting of a junction of three materials with different properties. Indeed, this magnetic system is composed by two distinct regions (racetracks) connected by a thin interface: the first region (termed sector 1) has isotropic in-plane magnetic chirality and supports skyrmion (S) excitations while the second (sector 3) has anisotropic chirality and
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Perpendicular magnetic anisotropy in half-metallic thin-film Co2CrAl J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Ryan Carlile, Juliana Herran, Shashi Poddar, Eric J Montgomery, Parashu Kharel, Paul M Shand, Pavel V Lukashev
Magnetocrystalline anisotropy (MCA) is one of the key parameters investigated in spin-based electronics (spintronics), e.g. for memory applications. Here, we employ first-principles calculations to study MCA in thin film full Heusler alloy Co2CrAl. This material was studied in the past, and has been reported to exhibit half-metallic electronic structure in bulk geometry. In our recent work, we showed
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Metal–insulator transition in epitaxial Ga-doped ZnO films via controlled thickness J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Joynarayan Mukherjee, B R K Nanda, M S Ramachandra Rao
Understanding and tuning of metal–insulator transition (MIT) in oxide systems is an interesting and active research topics of condensed matter physics. We report thickness dependent MIT in Ga-doped ZnO (Ga:ZnO) thin films grown by pulsed laser deposition technique. From the electrical transport measurements, we find that while the thinnest film (6 nm) exhibits a resistivity of 0.05 Ω cm, lying in the
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Non-hydrostatic pressure-dependent structural and transport properties of BiCuSeO and BiCuSO single crystals J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Yang-Yang Lv, Yonghui Zhou, Lu Xu, Yecheng Luo, Yan-Yan Zhang, Lin Cao, Jian Zhou, Y B Chen, Shu-Hua Yao, Shan-Tao Zhang, Zhaorong Yang, Yan-Feng Chen
High-pressure experiments usually expect a hydrostatic condition, in which the physical properties of materials can be easily understood by theoretical simulations. Unfortunately, non-hydrostatic effect is inevitable in experiments due to the solidification of the pressure transmitting media under high pressure. Resultantly, non-hydrostaticity affects the accuracy of the experimental data and sometimes
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The realization of quantum anomalous Hall effect in two dimensional electron gas J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Hua-rui Wu, Bing-lan Wu, Shu-guang Cheng, Hua Jiang
The quantum anomalous Hall effect (QAHE), carrying dissipationless chiral edge states, occurs without any magnetic field. Two main strategies were proposed to host QAHE: the magnetic topological insulator thin films and graphene systems. Only the former one was realized in experiment at low temperature. In this paper, by dealing with the two-dimensional electron gas with an anti-dot lattice, a realistic
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Decoupling between metal–insulator transition and structural phase transition in an interface-engineered VO2 J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Yanda Ji, Lei Cheng, Ning Li, Ye Yuan, Weizheng Liang, Hao Yang
The coupling between the metal–insulator transition (MIT) and the structural phase transition (SPT) in VO2 has been at the center of discussion for several decades, while the underlying mechanisms of electron–lattice or electron–electron interactions remain an open question. Until recently, the equilibrium state VO2 is believed to be a non-standard Mott–Hubbard system, i.e., both of the two interactions
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Damping via the hyperfine interaction of a spin-rotation mode in a two-dimensional strongly magnetized electron plasma J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 S Dickmann
We address damping of a Goldstone spin-rotation mode emerging in a quantum Hall ferromagnet due to laser pulse excitation. Recent experimental data show that the attenuation mechanism, dephasing of the observed Kerr precession, is apparently related not only to spatial fluctuations of the electron Land factor in the quantum well, but to a hyperfine interaction with nuclei, because local magnetization
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Electron–phonon coupling in APd3O4: A = Ca, Sr, and Sr0.85Li0.15 J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Bommareddy Poojitha, B H Reddy, Aprajita Joshi, Ankit Kumar, Asif Ali, R S Singh, Surajit Saha
Here we have investigated the role of electron phonon coupling on the Raman spectrum of narrow bandgap semiconductors APd3O4 (A = Ca, Sr) and hole-doped system Sr0.85Li0.15Pd3O4. Four Raman active phonons are observed at room temperature for all three compounds as predicted by factor group analysis. The lowest energy phonon (∼190/202cm−1) associated with Pd vibrations is observed to exhibit an asymmetric
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Electron–phonon coupling enhancement and displacive magnetostructural transition in SrCr2 As2 under magneto-Raman spectroscopy J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 U F Kaneko, M D Teodoro, P F Gomes, N S Sangeetha, D C Johnston
A Raman spectroscopy study on high quality single crystals of SrCr2 As2 (SCA) in the temperature T range 4K < T < 300K and high applied magnetic fields up to H = 9T is presented. The chromium B 1g phonon analysis reveals two anomalous shifts in the frequency, the first below T = 250K at H = 0T in the saturated AFM G-type order likely due to an enhanced electron–phonon coupling by the magnetic order
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Tunneling magnetoresistance in ensembles of ferromagnetic granules with exchange interaction and random easy axes of magnetic anisotropy J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Y M Beltukov, V I Kozub, A V Shumilin, N P Stepina
We study the tunneling magnetoresistance in the ensembles of ferromagnetic granules with random easy axes of magnetic anisotropy taking into account the exchange interaction between granules. It is shown that due to the exchange interaction magnetoresistance is effectively decoupled from magnetization, i.e. the strongest negative magnetoresistance can be observed at the field where magnetization is
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The spin-polarized edge states of blue phosphorene nanoribbons induced by electric field and electron doping J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Shidong Zhang, Yun Li, Yun-Peng Wang, Jialin Li, Mingjun Li, Mengqiu Long
Edge states of various two-dimensional materials such as graphene are intrinsically spin-polarized. In other materials, electric field and charge doping are required for introducing magnetism to their edges. In this work, by using first-principles calculations, we studied the effects of transverse electric field on the edge states of the armchair blue phosphorene nanoribbon (ABPNR), and found that
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Collective excitations in spin-polarized bilayer graphene J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Nguyen Van Men, Nguyen Quoc Khanh, Dong Thi Kim Phuong
We calculate the plasmon frequency ω and damping rate γ of plasma oscillations in a spin-polarized BLG system. Using the long wavelength approximation for dynamical dielectric function, we obtain an analytical expression for plasmon frequency showing that degree of spin polarization P has negligible effect on the long wavelength plasmon frequency. Numerical calculations demonstrate that the plasmon
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Selecting ‘convenient observers’ to probe the atomic structure of CVD graphene on Ir(111) via photoelectron diffraction J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Lucas Barreto, Luis Henrique de Lima, Daniel Coutinho Martins, Caio Silva, Rodrigo Cezar de Campos Ferreira, Richard Landers, Abner de Siervo
CVD graphene grown on metallic substrates presents, in several cases, a long-range periodic structure due to a lattice mismatch between the graphene and the substrate. For instance, graphene grown on Ir(111), displays a corrugated supercell with distinct adsorption sites due to a variation of its local electronic structure. This type of surface reconstruction represents a challenging problem for a
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Viscous properties of nickel-containing binary metal melts J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 R M Khusnutdinoff, R R Khairullina, A L Beltyukov, V I Lad’yanov, A V Mokshin
The paper presents the results of molecular dynamics study of the viscosity of nickel-containing binary metal melts for a wide range of temperatures, including the region of the equilibrium liquid phase and supercooled melt. It is shown that the temperature dependencies of the viscosity of binary metal melts are described by the Kelton’s quasi-universal model. Based on the analysis of the viscosity
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Hydrodynamic effects in the capture of rod-like molecules by a nanopore J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Radost Waszkiewicz, Maciej Lisicki
In the approach of biomolecules to a nanopore, it is essential to capture the effects of hydrodynamic anisotropy of the molecules and the near-wall hydrodynamic interactions which hinder their diffusion. We present a detailed theoretical analysis of the behaviour of a rod-like molecule attracted electrostatically by a charged nanopore. We first estimate the time scales corresponding to Brownian and
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Tracing the ionic evolution during ILG induced phase transformation in strontium cobaltite thin films J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Lei Gao, Xiaokun Chen, Xiangyu Lyu, Guiping Ji, Zhanfen Chen, Mingtong Zhu, Xun Cao, Chaorong Li, Ailing Ji, Zexian Cao, Nianpeng Lu
Ionic liquid gating (ILG) that drives the ions incorporate into or extract from the crystal lattice, has emerged as a new pathway to design materials. Although many intriguing emergent phenomena, novel physical properties and functionalities have been obtained, the gating mechanism governing the ion and charge transport remains unexplored. Here, by using the model system of brownmillerite SrCoO2.5
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The effect of Cu additions in FePt–BN–SiO2 heat-assisted magnetic recording media J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Robert Streubel, Alpha T N’Diaye, Kumar Srinivasan, Alan Kalitsov, Shikha Jain, Antony Ajan, Peter Fischer
Structural and chemical order impact magnetic properties of solids, which are governed by spin–orbit coupling and exchange interaction. The ordered L10 phase of FePt is a key material to heat-assisted magnetic recording; to enable high storage density, a solid understanding is needed of structural and chemical disorder at small length scales, as well as associated modifications of the electronic band
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Structural tuning for enhanced magnetic performance by Y substitution in FeB-based metallic glasses J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 Guangcun Shan, Xin Li, Haoyi Tan, Chan-Hung Shek, Jiliang Zhang
Despite the compositional analogue to Fe71B17(NbYZr)12 metallic glass, the Fe71B17Y12 metallic glass has a saturated magnetization of Ca 108 emu g−1, more than 5 times of that in Fe71B17(NbYZr)12 (20 emu g−1). The structural origin for such significant difference in magnetic performance was investigated by x-ray absorption fine structure spectra and ab initio molecular dynamics (AIMD) simulations including
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Electronic and topological properties of group-10 transition metal dichalcogenides J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-11 M K Hooda, C S Yadav, D Samal
The group 10 transition metal dichalcogenides (TMDs) (MX 2: M = Ni, Pd, Pt; X = S, Se, Te) have attracted much attention in the last few decades because of observation of exotic phases and phenomena such as superconductivity (SC), topological surface states (TSSs), type II Dirac fermions, helical spin texture, Rashba effect, 3D Dirac plasmons, metal–insulator transitions, charge density waves (CDW)
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Modeling of vortex dynamics in HTSs with defects under the impact of pulsed magnetic field J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-10 A N Moroz, V A Kashurnikov, I A Rudnev, A N Maksimova
By means of the Monte Carlo method, a numerical study of the vortex system in a high-temperature superconductor under the impact of pulses of magnetic field has been conducted. Various shapes and amplitudes of pulses have been considered. Samples with random and regular distributions of three different numbers of defects have been compared from the viewpoint of efficiency of flux trapping. The low-temperature
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Q = 0 order in quantum kagome Heisenberg antiferromagnet J. Phys. Condens. Matter (IF 2.707) Pub Date : 2021-02-10 Kallol Mondal, Charudatt Kadolkar
We have studied the nearest neighbor Heisenberg model with added Dzyaloshinskii–Moriya interaction using Schwinger boson mean-field theory considering the in-plane component as well as out-of-plane component. Motivated by the experimental result of vesignieite that the ground state is in a Q = 0 long-range order state, we first looked at the classical ground state of the model and considered the mean-field
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