Journal of Physics: Condensed Matter最新文献_第9页

Enhancement of ferroelectric polarization in Sm-doped BaFe_0.2Ti_0.8O₃ceramics. sm掺杂BaFe0.2Ti0.8O3陶瓷的铁电极化增强

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2025-04-04 DOI: 10.1088/1361-648X/adc52d

Anumeet Kaur, Arkaprava Das, Trilokchand L Kumavat, Wei-Hsiang Huang, Surbhi Gupta, Joseph Vimal Vas, Chi-Liang Chen, Asokan Kandasami, Deobrat Singh, Yogesh Sonvane

{"title":"Enhancement of ferroelectric polarization in Sm-doped BaFe0.2Ti0.8O3ceramics.","authors":"Anumeet Kaur, Arkaprava Das, Trilokchand L Kumavat, Wei-Hsiang Huang, Surbhi Gupta, Joseph Vimal Vas, Chi-Liang Chen, Asokan Kandasami, Deobrat Singh, Yogesh Sonvane","doi":"10.1088/1361-648X/adc52d","DOIUrl":"10.1088/1361-648X/adc52d","url":null,"abstract":"We show progressive enhancement in ferroelectric polarization with increasing Sm doping concentration along with retrieving tetragonality from the hexagonal paraelectric phase for Ba1-xSmxFe0.2Ti0.8O3(BTO) solid solution (x= 0, 0.10, 0.15, 0.20). The cooperative off-centering phenomenon due to octahedral distortion promotes interpolar clustering resulting in the formation of polar nano region causing an enhancement in saturation polarization and coercive field with Sm doping. Ferroelectric domain fringes observed in scanning and transmission electron microscopic images indicate the presence of ferroelectric ordering for the highest Sm-doped compound. Formation ofSmBa∘-FeTi'defect complex results in a reduction of oxygen vacancy (VO) defects which is observed from x-ray photoelectron spectroscopy. The reduction in VOimproves the domain switching by domain wall depinning and facilitates the increment in saturation polarization with Sm doping. The x-ray absorption spectra at TiL3,2edges show the increase oft2gegratio indicating enhanced Ti 3d-O 2porbital hybridization which is supported by DFT calculation. This DFT calculation also confers that the increment in Ti 3d/Sm 4d-O 2porbital hybridization further weakens the short-range repulsion between core orbitals and facilitates the enhancement of saturation polarization.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143710389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Frustration-induced skyrmion crystals in centrosymmetric magnets. 中心对称磁体中受挫诱导的斯基米子晶体。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2025-04-04 DOI: 10.1088/1361-648X/adbf5b

Hikaru Kawamura

{"title":"Frustration-induced skyrmion crystals in centrosymmetric magnets.","authors":"Hikaru Kawamura","doi":"10.1088/1361-648X/adbf5b","DOIUrl":"10.1088/1361-648X/adbf5b","url":null,"abstract":"Recent theoretical and experimental studies on the frustration-induced skyrmion crystal (SkX) in centrosymmetric magnets are reviewed, with some emphasis on their symmetry and topological aspects. Special importance of frustration and chirality is highlighted. Theories cover the studies based on both the spin models and the electronic models. In the former, the frustrated Heisenberg models on the triangular or the square lattices interacting either via the long-range RKKY interaction or via the competing short-range exchange interactions are treated, where frustration is borne by the oscillating nature of the long-range RKKY interaction or by the competition between the shorter-range exchange interactions. Special attention is paid to the role played by the magnetic anisotropy including the dipolar interaction. The electronic models discussed are mainly the Kondo lattice model on the triangular lattice, which reduces to the RKKY Heisenberg in the weak-coupling limit. Experiments on centrosymmetric SkX-hosting magnets cover the hexagonal or trigonal magnets Gd2PdSi3(triangular) and Gd3Ru4Al12(breathing kagome), and the tetragonal magnets GdRu2Si2and EuAl4. Various experimental data, including magnetization or susceptibility, specific heat, Hall resistivity, resonant magneticx-ray scattering, neutron scattering, Lorentz transmission electron microscopy, etc are reviewed and discussed in conjunction with the theoretical results. The nature of a variety of phases surrounding the SkX phase in the phase diagram, many of which are of multiple-qcharacter, is also examined. Finally, some discussion is given about the physical origin of the centrosymmetric SkX formation, its unique features in comparison with the non-centrosymmetric SkX induced by the antisymmetric Dzaloshinskii-Moriya interaction, together with some open and challenging problems for the future.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143605266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ultra-wide band gap and large exciton effect in 2D ferrovalley material H-FeCl₂. 二维铁谷材料H-FeCl2的超宽带隙和大激子效应。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2025-04-04 DOI: 10.1088/1361-648X/adc4a8

Chaobo Luo, Daxiang Chen, Zongyu Huang, Wenchao Liu, Zhihui Jiang, Landong Xiao, Gencai Guo, Xiang Qi, Xiangyang Peng

{"title":"Ultra-wide band gap and large exciton effect in 2D ferrovalley material H-FeCl2.","authors":"Chaobo Luo, Daxiang Chen, Zongyu Huang, Wenchao Liu, Zhihui Jiang, Landong Xiao, Gencai Guo, Xiang Qi, Xiangyang Peng","doi":"10.1088/1361-648X/adc4a8","DOIUrl":"10.1088/1361-648X/adc4a8","url":null,"abstract":"Ferrovalley materials are valleytronic materials with intrinsic ferromagnetism, in which the presence of spontaneous valley polarization is more conducive to practical applications. The optical properties of ferrovalley are important for selectively exciting electrons at the valley. In this paper, the electronic and optical spectrum of the H-phase FeCl2monolayer is studied using first-principles calculations as an example. We use hybrid functional HSE06 and GW0methods with spin-orbit coupling for our calculations, the band gap of H-FeCl2is about 3.975 and 4.072 eV at K and -K valley, which is significantly larger than that obtained by the PBE method, with a 97 meV valley splitting. It is shown that the monolayer H-FeCl2is a ferrovalley material with an ultra-wide band gap and large intrinsic valley polarization, which has strong electronic correlation and many-body effects. Calculation of the imaginary part of the dielectric function using GW-BSE method shows that the energy corresponding to the exciton peak is 2.421 and 2.491 eV, much smaller than the GW band gap. The exciton binding energy is about 1.554 and 1.581 eV at K and -K valley, indicating a large exciton effect. And the exciton binding energy of the two valleys are unequal, with a difference of 27 meV. It is found that splitting occurs at the first exciton peak in the ferrovalley material, and the splitting value is inequivalent to the bandgap splitting at the valley, which is instructive for further research as well as application of the valleytronics.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143700814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Approaches to tunnel magnetoresistance effect with antiferromagnets. 反铁磁体隧道磁阻效应的研究。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2025-04-02 DOI: 10.1088/1361-648X/adc05e

Katsuhiro Tanaka, Takuya Nomoto, Ryotaro Arita

{"title":"Approaches to tunnel magnetoresistance effect with antiferromagnets.","authors":"Katsuhiro Tanaka, Takuya Nomoto, Ryotaro Arita","doi":"10.1088/1361-648X/adc05e","DOIUrl":"10.1088/1361-648X/adc05e","url":null,"abstract":"The tunnel magnetoresistance (TMR) effect is one of the representative phenomena in spintronics. Ferromagnets, which have a net spin polarization, have been utilized for the TMR effect. Recently, by contrast, the TMR effect with antiferromagnets, which do not possess a macroscopic spin polarization, has been proposed, and also been observed in experiments. In this topical review, we discuss recent developments in the TMR effect, particularly focusing on the TMR effect with antiferromagnets. First, we review how the TMR effect can occur in antiferromagnetic tunnel junctions. The Julliere model, which has been conventionally utilized to grasp the TMR effect with ferromagnets, breaks down for the antiferromagnetic TMR effect. Instead, we see that the momentum dependent spin splitting explains the antiferromagnetic TMR effect. After that, we revisit the TMR effect from viewpoint of the local density of states (LDOS). We particularly focus on the LDOS inside the barrier, and show that the product of the LDOS will qualitatively capture the TMR effect not only in the ferromagnetic tunnel junctions but also in the ferrimagnetic and antiferromagnetic tunnel junctions. This method is expected to work usefully for designing magnetic tunnel junctions.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143625034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Magnetic texture enabled electrical control of Dzyaloshinskii-Moriya interaction in a Weyl semimetal. Weyl半金属中Dzyaloshinskii-Moriya相互作用的磁织构电子控制。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2025-04-01 DOI: 10.1088/1361-648X/adc4a9

Yuriy G Semenov, Ki Wook Kim

{"title":"Magnetic texture enabled electrical control of Dzyaloshinskii-Moriya interaction in a Weyl semimetal.","authors":"Yuriy G Semenov, Ki Wook Kim","doi":"10.1088/1361-648X/adc4a9","DOIUrl":"10.1088/1361-648X/adc4a9","url":null,"abstract":"Purely electrical control of the Dzyaloshinskii-Moriya interaction (DMI) without any external magnetic field is explored in a magnetic Weyl semimetal (WSM). The underlying mechanism for the DMI in the WSM is the recently identified asymmetrical indirect spin-spin interaction compatible with the inversion symmetry of the structure. While the necessary imbalance in the fermion population of opposite chirality is normally achieved with non-orthogonal external electric and magnetic fields (i.e. the axial anomaly), it is found that the intrinsic axial magnetic field characteristic to an inhomogeneous magnetic texture can play the role of the magnetic field. When applied to the magnetic domain walls as specific examples, our theoretical analysis clearly illustrates that the resulting DMI is pinned by and can in turn significantly affect the wall textures. As the appearance and strength of the DMI can be solely controlled by the applied electric field, this mechanism enables electrical modulation of magnetic domains including their excitation in the WSMs. Numerical calculations highlight significant advantages of the WSM over the conventional magnetic materials in spintronic applications such as the racetrack memory.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143700803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental and theoretical investigation of strongly correlated antiferromagnet NdBiTe. 强相关反铁磁体NdBiTe的实验与理论研究。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2025-04-01 DOI: 10.1088/1361-648X/adc231

Prabuddha Kant Mishra, Shivani Kumawat, Soumyakanta Panda, Niharika Mohapatra, B K Mani, Ashok Kumar Ganguli

{"title":"Experimental and theoretical investigation of strongly correlated antiferromagnet NdBiTe.","authors":"Prabuddha Kant Mishra, Shivani Kumawat, Soumyakanta Panda, Niharika Mohapatra, B K Mani, Ashok Kumar Ganguli","doi":"10.1088/1361-648X/adc231","DOIUrl":"10.1088/1361-648X/adc231","url":null,"abstract":"The ZrSiS-class of layered materials offer interesting topological and magnetic characteristics suitable for spintronics applications. In this work, we have synthesized a polycrystalline NdBiTe using solid-state reaction technique and have examined the magnetic properties in 2-300 K temperature range using temperature and field-dependent magnetization measurements. Our magnetic and specific heat data demonstrates a long-range antiferromagnetic (AFM) ordering in the material below 4.5 K. Furthermore, our isothermal magnetization data show a signature of spin-reorientation below Neel temperature. The observed nonlinearity in inverse susceptibility vs temperature data, and a hump in specific heat in 5-20 K range, indicate the existence of crystal field splitting in the material. Our transport properties measurements show the metallic behavior with positive magnetoresistance in the temperature range of 2-300 K. The observed rise in resistivity as function of temperature below Neel temperature infers the strongly correlated fermions, which is consistent with the observed large Sommerfeld coefficient. Consistent with experimental results, our first-principles calculations predict an AFM semimetallic nature of NdBiTe. Further, our spin-orbit coupled simulations of electronic structure show a signature of weak topological nature of the material.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143657576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Resistively detected electron spin resonance andg-factor in few-layer exfoliated MoS₂devices. 少层剥离二硫化钼器件中电阻检测的电子自旋共振和因子。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2025-04-01 DOI: 10.1088/1361-648X/adc35d

Chithra H Sharma, Appanna Parvangada, Lars Tiemann, Kai Rossnagel, Jens Martin, Robert H Blick

引用次数: 0

Tunable higher-order non-Hermitian skin effect in the SSH topolectrical circuits. SSH拓扑电路中可调谐的高阶非厄米集肤效应。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2025-03-31 DOI: 10.1088/1361-648X/adc35b

Lebin Wang, Wei Lin, Banxian Ruan, Yuanjiang Xiang, Xiaoyu Dai

引用次数: 0

Unraveling the topological phase in Zintl semiconductors RbZn₄X₃(X = P, As) through band engineering. 利用能带工程揭示Zintl半导体RbZn4X3 （X=P, As）的拓扑相。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2025-03-31 DOI: 10.1088/1361-648X/adc17e

Ramesh Kumar, Rajesh Kumar, Antik Sihi, Mukhtiyar Singh

{"title":"Unraveling the topological phase in Zintl semiconductors RbZn4X3(X = P, As) through band engineering.","authors":"Ramesh Kumar, Rajesh Kumar, Antik Sihi, Mukhtiyar Singh","doi":"10.1088/1361-648X/adc17e","DOIUrl":"10.1088/1361-648X/adc17e","url":null,"abstract":"We report the topological phase transition (TPT) in compounds of relatively less explored Zintl family RbZn4X3(X = P, As) viafirst-principlescalculation. These intermetallic compounds have already been experimentally synthesized in aKCu4S3-typetetragonal structure (P4/mmm) and reported to have a topologically trivial semimetallic nature with a direct band gap. We thoroughly studied the electronic structure, stability of RbZn4X3(X = P, As) and demonstrated the TPTs in these materials with external applied pressure and epitaxial strain. The dynamical and mechanical stabilities of these compounds are verified through phonon dispersion and Born stability criteria at ambient and TPT pressure/strain. A topologically non-trivial phase in RbZn4P3(RbZn4As3) is observed at 45 GPa (38 GPa) of hydrostatic pressure and 10% (8%) of epitaxial strain. This non-trivial phase is identified by band inversion betweenZn-sandP/As-pzorbitalsin the bulk band structure of these materials which is further confirmed using the surface density of states and Fermi arc contour in(001)-plane. The ℤ2topological invariants (ν0; ν1ν2ν3) for these materials are calculated using the product of parities of all filled bands (Kane and Mele model) and the evolution of Wannier charge centers (Wilson loop method). The change in values of (ν0; ν1ν2ν3) from (0; 000) to (1; 000), at the particular values of pressure and strain, is another signature of the TPT in these materials.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143649435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hysteresis and pyroelectric behaviour at isomorphic transition in green CsSnI₃. 绿色CsSnI3在同构跃迁中的迟滞和热释电行为。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2025-03-31 DOI: 10.1088/1361-648X/adbead

Prem C Bharti, Priyanka A Jha, Pardeep K Jha, Prabhakar Singh

{"title":"Hysteresis and pyroelectric behaviour at isomorphic transition in green CsSnI3.","authors":"Prem C Bharti, Priyanka A Jha, Pardeep K Jha, Prabhakar Singh","doi":"10.1088/1361-648X/adbead","DOIUrl":"10.1088/1361-648X/adbead","url":null,"abstract":"Lead-free perovskite halide CsSnI3has emerged as a promising material for optoelectronic applications due to its direct bandgap (1.3-1.4 eV), high charge carrier mobility, and strong visible-spectrum absorption. Among its polymorphs, the green phase, with a favorable bandgap of ∼1.24 eV, demonstrates enhanced structural stability and resistance to phase degradation under ambient conditions. In this study, we investigate the green polymorph of CsSnI3and observe pyroelectric behavior, indicative of ferroelectric-like properties despite its globally centrosymmetric (Pa3-) cubic structure. Utilizing Piezo-force microscopy, dielectric measurements, impedance spectroscopy, and Raman spectroscopy, we identified local non-centrosymmetry influencing hysteresis and conduction properties. Impedance spectroscopy further reveals the interaction of grains and grain boundaries under a low AC electric field, both before and after light exposure and poling. A reduction in relaxation time with increasing temperature in poled samples is observed, while the combined effects of light exposure and poling result in an increased relaxation time. Our results indicate that local non-centrosymmetry plays a critical role in influencing hysteresis and conduction behavior. These findings highlight the importance of phase transitions and vibrational mode dynamics in optimizing the performance of CsSnI3-based devices, paving the way for their broader application in advanced optoelectronic technologies.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143597159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0