Journal of Physics: Condensed Matter最新文献_第3页

Machine learning assisted crystallographic reconstruction from atom probe tomographic images. 机器学习辅助原子探针断层扫描图像的晶体学重建。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2024-10-30 DOI: 10.1088/1361-648X/ad81a2

Jie-Ming Pu, Shuai Chen, Tong-Yi Zhang

{"title":"Machine learning assisted crystallographic reconstruction from atom probe tomographic images.","authors":"Jie-Ming Pu, Shuai Chen, Tong-Yi Zhang","doi":"10.1088/1361-648X/ad81a2","DOIUrl":"10.1088/1361-648X/ad81a2","url":null,"abstract":"Atom probe tomography (APT) is a powerful technique for three-dimensional (3D) atomic-scale imaging, enabling the accurate analysis on the compositional distribution at the nanoscale. How to accurately reconstruct crystallographic information from APT data, however, is still a great challenge due to the intrinsic nature of the APT technique. In this paper, we propose a novel approach that consists of the modified forward simulation process and the backward machine learning process to recover the tested crystal from APT data. The high-throughput forward simulations on Al single crystals of different orientations generate 10 000 original 3D images and data augmentation is implemented on the original images, resulting in 100 000 3D images. The big data allows the development of deep learning models and three deep learning algorithms of Convolutional Neural Network (CNN), Vision Transformer (ViT), and Variational Autoencoder (VAE) are used in the backward process. After training, the ViT model performs superior than the CNN and VAE models, which can recover the crystalline orientation outstandingly, as evaluated by the coefficient of determinationR2and the Mean Percent Error (MPE), viz.,R2= 0.93 and MPE = 0.43%,R2= 0.97 and MPE = 0.35%, andR2= 0.93 and MPE = 0.77% for the rotation anglesϕ,ψandθ, respectively, on the test dataset. The present work clearly demonstrates the capability of deep learning models in the recovery of the tested crystals from APT data, thereby paving the way for the further development of large artificial intelligent models of APT.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142348883","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

Tight-binding model of Pt-based jacutingaites as combination of the honeycomb and kagome lattices. 铂基贾库泰特的紧密结合模型--蜂巢晶格与卡戈米晶格的结合。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2024-10-30 DOI: 10.1088/1361-648X/ad8853

G Santos-Castro, L K Teles, I Guilhon Mitoso, J M Pereira

引用次数: 0

Superconducting Energy Gap Structure of CsV₃Sb₅from Magnetic Penetration Depth Measurements. 从磁穿透深度测量看 CsV3Sb5 的超导能隙结构

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2024-10-30 DOI: 10.1088/1361-648X/ad8d2b

Morgan James Grant, Yi Liu, Guanghan Cao, Joseph Alec Wilcox, Yanfeng Guo, Xiaofeng Xu, Antony Carrington

{"title":"Superconducting Energy Gap Structure of CsV3Sb5from Magnetic Penetration Depth Measurements.","authors":"Morgan James Grant, Yi Liu, Guanghan Cao, Joseph Alec Wilcox, Yanfeng Guo, Xiaofeng Xu, Antony Carrington","doi":"10.1088/1361-648X/ad8d2b","DOIUrl":"https://doi.org/10.1088/1361-648X/ad8d2b","url":null,"abstract":"Experimental determination of the structure of the superconducting order parameter in the kagome lattice compound CsV3Sb5is an essential step towards understanding the nature of the superconducting pairing in this material. Here we report measurements of the temperature dependence of the in-plane magnetic penetration depth, λ(T), in crystals of CsV3Sb5down to ∼ 60 mK. We find that λ(T) is consistent with a fully-gapped state but with significant gap anisotropy. The magnitude of the gap minima obtained are 0.16kBTcand 0.21kBTcfor the measured samples, markedly smaller than previous estimates. We discuss different forms of potential anisotropy and how these can be linked to the V and Sb Fermi surface sheets. We highlight a significant discrepancy between the calculated and measured values of λ(T=0) which we suggest is caused by spatially suppressed superconductivity.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142546086","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

Floquet engineering of interparticle correlations in electron-hole few-body system for strong radial confinement. 强径向约束电子-空穴几体系统中粒子间相关性的 Floquet 工程。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2024-10-30 DOI: 10.1088/1361-648X/ad882c

G Dziembaj, T Chwiej

{"title":"Floquet engineering of interparticle correlations in electron-hole few-body system for strong radial confinement.","authors":"G Dziembaj, T Chwiej","doi":"10.1088/1361-648X/ad882c","DOIUrl":"10.1088/1361-648X/ad882c","url":null,"abstract":"We investigate the effects of off-resonant THz-frequency laser light coupling to bound few-body electron-hole system, i.e. the exciton and negatively charged trion confined in quantum wire. To solve this problem, we first conduct a unitary Hennerberger-Kramers transformation of the Hamiltonian and diagonalize its perturbative approximation to obtain the exciton and trion Floquet states. Within this framework, the light-matter coupling renormalizes an attractiveehinteraction, leaving the repulsiveeeunchanged, thus modifying corresponding two-particle correlation energies. Generally, the correlation energy ofehwould exceed theeeone for a semiconductor material with strongly localized heavy holes. However, as the former is weakened by increasing laser intensity, this relation can be reversed. Consequently, the trion may dissociate unconventionally, the hole gradually decouples from still strongly interacting electrons, and adequate energy and optical spectra changes accompany this process. The energy levels of the exciton and trion Floquet states are raised, while their optical brightness smoothly decreases for stronger laser intensities. We also show this process can be further modified by breaking the mirror symmetry of wire with a static electric field, and then the occurrence of the avoided crossings between the lowest energy levels of the trion depends on the laser intensity. These anticrossings shall be observed experimentally, confirming thus the usefulness of Floquet engineering for fast manipulations of the few-particle states in electron-hole systems on a subpicosecond time scale.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142468304","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

Exploring Magnetic Disorder in Inverted Core-Shell Nanoparticles: The Role of Surface Anisotropy and Core/Shell Coupling. 探索倒核壳纳米粒子中的磁紊乱：表面各向异性和核/壳耦合的作用

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2024-10-30 DOI: 10.1088/1361-648X/ad8d2a

Dámaso Laura, Emilio De Biasi

{"title":"Exploring Magnetic Disorder in Inverted Core-Shell Nanoparticles: The Role of Surface Anisotropy and Core/Shell Coupling.","authors":"Dámaso Laura, Emilio De Biasi","doi":"10.1088/1361-648X/ad8d2a","DOIUrl":"https://doi.org/10.1088/1361-648X/ad8d2a","url":null,"abstract":"In this work, we have studied the effect of internal coupling in magnetic nanoparticles with inverted core-shell structure (antiferromagnet-ferrimagnet) and also magnetic surface anisotropy, performing Monte Carlo simulations based on a micromagnetic model applied in the limit of lattice size equal to the crystalline unit cell. In the treatment, different internal regions of the particle were labeled in order to analyze the magnetic order and the degree of coupling between them. The results obtained are in agreement with experimental observations in CoO/CoFe2O4 and ZnO/CoFe2O systems, which we have taken as reference. It is observed that the surface anisotropy decreases the coercive field and the blocking temperature of the system. However, the core/shell coupling improves these properties and magnetically hardens the system. Our study shows that a significant magnetic stress is generated in the system, leading to magnetic disorder in the spins of the particle interface. On the other hand, in cases of high surface anisotropy, within a range of interfacial exchange values, a clear magnetic disorder is observed in the shell, which leads to anomalous behavior because the magnetization reversal process is no longer coherent.&#xD.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142546085","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

Strain induced phase transitions and hysteresis in aluminium nitride: a density functional theory study. 氮化铝中的应变诱导相变和滞后：密度泛函理论研究。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2024-10-30 DOI: 10.1088/1361-648X/ad8852

O Namir, J Chen, I Belabbas

{"title":"Strain induced phase transitions and hysteresis in aluminium nitride: a density functional theory study.","authors":"O Namir, J Chen, I Belabbas","doi":"10.1088/1361-648X/ad8852","DOIUrl":"10.1088/1361-648X/ad8852","url":null,"abstract":"Computer atomistic simulations based on density functional theory were carried out to investigate strain induced phase transitions in aluminium nitride (AlN). The wurtzite to graphitic and graphitic to wurtzite transformations were investigated at the atomic level and their physical origins were identified. Both phase transitions were found to be of the first order. The wurtzite to graphitic phase transition takes place in the tensile regime at a strain value of +7%. The driving force for this transformation was identified to be an elastic instability induced by tensile strain. A hysteresis was demonstrated where the graphitic structure is separated from the wurtzite by a kinetic energy barrier. The origin of the observed hysteresis is due to the asymmetry of bond formation and bond breaking associated with the wurtzite to graphitic and graphitic to wurtzite transitions, respectively. A dynamic instability taking place at +3%, along the graphitic path, prevents the hysteresis to fully occur. The possible occurrence of the hysteresis has then to be taken into account when growing the graphitic phase by heteroepitaxy. Otherwise, maintaining the graphitic structure at low strain, through the hysteresis, offers new possibilities in the development of novel future applications.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142468307","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

Evidence for nematic fluctuations in FeSe superconductor: a⁵⁷Fe Mössbauer spectroscopy study. FeSe 超导体中向列波动的证据：57Fe 莫斯鲍尔光谱研究。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2024-10-30 DOI: 10.1088/1361-648X/ad88c6

Shixin Hu, Jijun Xue, Xiaoying Wang, Hua Pang

{"title":"Evidence for nematic fluctuations in FeSe superconductor: a57Fe Mössbauer spectroscopy study.","authors":"Shixin Hu, Jijun Xue, Xiaoying Wang, Hua Pang","doi":"10.1088/1361-648X/ad88c6","DOIUrl":"10.1088/1361-648X/ad88c6","url":null,"abstract":"There has been controversy about the driving force of the nematic order in the FeSe superconductor. Here, we present a detailed study of the57Fe Mössbauer spectra of FeSe single-crystal powders, focusing on the temperature dependences of the hyperfine parameters in the vicinity of the nematic transition temperature,Ts∼ 90 K. The nematicity-induced splitting ofdxzanddyzbands, obtained from the anomalous increase in quadrupole splitting nearTs, starts at 143 K. The temperature evolution of the lattice dynamics, deduced from the recoilless fractions and second-order Doppler shifts, is found to undergo successively two segments of phonon-softening (160 K-105 K) and phonon-hardening (105 K-90 K), related to the appearance of local orthorhombic distortions aboveTsand the establishing way of the associated nematic correlations. Analysis of the linewidths shows that spin fluctuations occur not only below 70 K but also acrossTs(105 K-70 K), accompanied by the non-Fermi liquid behavior of the electrons. The results demonstrate the strong interactions between lattice, spin, and electron degrees of freedom in the vicinity ofTsand that the lattice degrees of freedom may play an essential role in driving the nematic order for FeSe.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142468303","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

Ab initio calculations of second-, third-, and fourth-order partial and inner elastic constants of diamond. 金刚石二阶、三阶和四阶部分和内部弹性常数的 Ab initio 计算。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2024-10-30 DOI: 10.1088/1361-648X/ad8d2c

Zhukun Zhou, Tangyan Chen, Yangzhou Liu, Hao Wang, Mo Li

引用次数: 0

Topological signatures of triply degenerate fermions in Heusler alloys: anab initiostudy. Heusler 合金中三重退格费米子的拓扑特征：一项 ab initio 研究。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2024-10-28 DOI: 10.1088/1361-648X/ad8715

Bhautik R Dhori, Aritri Mohanta, Prafulla K Jha

{"title":"Topological signatures of triply degenerate fermions in Heusler alloys: anab initiostudy.","authors":"Bhautik R Dhori, Aritri Mohanta, Prafulla K Jha","doi":"10.1088/1361-648X/ad8715","DOIUrl":"10.1088/1361-648X/ad8715","url":null,"abstract":"Triply degenerate nodal point (TP) fermions, lacking elementary particle counterparts, have been theoretically anticipated as quasiparticle excitations near specific band crossing points constrained by distinct space-group symmetries instead of Lorentz invariance. Here, based onfirst-principlescalculations and symmetry analysis, we demonstrate the presence of TP fermions in Heusler alloys. Furthermore, we predict that these Heusler alloys are dynamically stable, exhibiting TP fermions along four distinctC3axes in the F-43m space group. We show thatα-LiCaPdSb harbours peculiar Fermi arcs and surface states on the (111) and (001) crystal facets, owing to the coexistence of threefold rotational and time reversal symmetry. More interestingly, a modest tensile strain can increase the distance of fermions along the Γ-Lhigh symmetric line by as much as 21.10%, which give rise to measurable Fermi arcs. Furthermore, we investigate non-trivial topological insulator phase inβ-LiCaPdSb, by changing the chemical environment through placing transition metal atoms at various Wyckoff positions. Theβ-LiCaPdSb harbour a semi-metallic nature, and by breaking cubic symmetry, it undergoes a transition from semi-metal to a non-trivial topological insulator. In addition, for the first time, rare-earth LaPtBi half-Heusler alloy is examined under strain to uncover multiple band inversions associated with the TP fermionic phase. The observed multiple band inversion is entirely unaffected by spin-orbit coupling. We show that the LaPtBi compound hosts TP fermions, which are linked to aZ2topological invariant. Remarkably, with clear band crossings and multiple band inversion, we point out the possibilities of the LaPtBi for displaying a rich topological phase diagram. Our work provides a prototype material platform for experimental detection through angle-resolved photoemission spectroscopy or scanning tunnelling spectroscopy and practical spintronic applications.","PeriodicalId":16776,"journal":{"name":"Journal of Physics: Condensed Matter","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142468311","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

Unusual spin dynamics in the van der Waals antiferromagnet FeGa₂S₄. 范德华反铁磁体 FeGa2S4 中不寻常的自旋动力学。

IF 2.3 4区物理与天体物理

Journal of Physics: Condensed Matter Pub Date : 2024-10-28 DOI: 10.1088/1361-648X/ad861a

Yifei Tang, Yoshihiko Umemoto, Yo Kawamoto, Masahiro Kawamata, Shinichiro Asai, Yoichi Ikeda, Masaki Fujita, Yusuke Nambu

引用次数: 0