arXiv - PHYS - Superconductivity最新文献_第7页

Nodeless superconductivity and topological nodal states in molybdenum carbide 碳化钼中的无结点超导性和拓扑结点态

arXiv - PHYS - Superconductivity Pub Date : 2024-09-04 DOI: arxiv-2409.02380

Tian Shang, Yuting Wang, Bochen Yu, Keqi Xia, Darek J. Gawryluk, Yang Xu, Qingfeng Zhan, Jianzhou Zhao, Toni Shiroka

{"title":"Nodeless superconductivity and topological nodal states in molybdenum carbide","authors":"Tian Shang, Yuting Wang, Bochen Yu, Keqi Xia, Darek J. Gawryluk, Yang Xu, Qingfeng Zhan, Jianzhou Zhao, Toni Shiroka","doi":"arxiv-2409.02380","DOIUrl":"https://doi.org/arxiv-2409.02380","url":null,"abstract":"The orthorhombic molybdenum carbide superconductor with $T_c$ = 3.2 K was\u0000investigated by muon-spin rotation and relaxation ($mu$SR) measurements and by\u0000first-principle calculations. The low-temperature superfluid density,\u0000determined by transverse-field $mu$SR, suggests a fully-gapped superconducting\u0000state in Mo$_2$C, with a zero-temperature gap $Delta_0$ = 0.44 meV and a\u0000magnetic penetration depth $lambda_0$ = 291 nm. The time-reversal symmetry is\u0000preserved in the superconducting state, as confirmed by the absence of an\u0000additional muon-spin relaxation in the zero-field $mu$SR spectra.\u0000Band-structure calculations indicate that the density of states at the Fermi\u0000level is dominated by the Mo $4d$-orbitals, which are marginally hybridized\u0000with the C $2p$-orbitals over a wide energy range. The symmetry analysis\u0000confirms that, in the absence of spin-orbit coupling (SOC), Mo$_2$C hosts\u0000twofold-degenerate nodal surfaces and fourfold-degenerate nodal lines. When\u0000considering SOC, the fourfold-degenerate nodal lines cross the Fermi level and\u0000contribute to the electronic properties. Our results suggest that, similarly to\u0000other phases of carbides, also the orthorhombic transition-metal carbides host\u0000topological nodal states and may be potential candidates for future studies of\u0000topological superconductivity.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142210239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Josephson diode effect in one-dimensional quantum wires connected to superconductors with mixed singlet-triplet pairing 与单三态混合配对超导体相连的一维量子线中的约瑟夫森二极管效应

arXiv - PHYS - Superconductivity Pub Date : 2024-09-04 DOI: arxiv-2409.02794

Abhiram Soori

{"title":"Josephson diode effect in one-dimensional quantum wires connected to superconductors with mixed singlet-triplet pairing","authors":"Abhiram Soori","doi":"arxiv-2409.02794","DOIUrl":"https://doi.org/arxiv-2409.02794","url":null,"abstract":"The Josephson diode effect (JDE), characterized by asymmetric critical\u0000currents in a Josephson junction, has drawn considerable attention in the field\u0000of condensed matter physics. We investigate the conditions under which JDE can\u0000manifest in a one-dimensional Josephson junction composed of a\u0000spin-orbit-coupled quantum wire with an applied Zeeman field, connected between\u0000two superconductors. Our study reveals that while spin-orbit coupling (SOC) and\u0000a Zeeman field in the quantum wire are not sufficient to induce JDE when the\u0000superconductors are purely singlet, the introduction of triplet pairing in the\u0000superconductors leads to the emergence of JDE. This finding highlights the\u0000potential of JDE as a probe for triplet superconductivity. We further\u0000demonstrate that even in absence of SOC in the quantum wire, JDE can arise when\u0000the directions of the triplet pairing and the Zeeman field are non-collinear,\u0000provided the superconductors exhibit mixed singlet-triplet pairing.\u0000Additionally, we identify specific conditions under which JDE is absent,\u0000namely, when the pairing is purely triplet and the directions of the SOC and\u0000the triplet pairing are perpendicular. Our findings indicate that JDE is always\u0000accompanied by the anomalous Josephson effect. The diode effect coefficient is\u0000found to oscillate with variations in the chemical potential of the quantum\u0000wire, driven by Fabry-P'erot interference effects. Our results suggest that\u0000quantum wires in Josephson junctions could serve as effective platforms for\u0000probing triplet superconductivity through the observation of JDE.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142210237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ephemeral Superconductivity Atop the False Vacuum 假真空之上的短暂超导现象

arXiv - PHYS - Superconductivity Pub Date : 2024-09-04 DOI: arxiv-2409.02992

Gal Shavit, Stevan Nadj-Perge, Gil Refael

{"title":"Ephemeral Superconductivity Atop the False Vacuum","authors":"Gal Shavit, Stevan Nadj-Perge, Gil Refael","doi":"arxiv-2409.02992","DOIUrl":"https://doi.org/arxiv-2409.02992","url":null,"abstract":"A many body system in the vicinity of a first-order phase transition may get\u0000trapped in a local minimum of the free energy landscape. These so-called\u0000false-vacuum states may survive for exceedingly long times if the barrier for\u0000their decay is high enough. The rich phase diagram obtained in graphene\u0000multilayer devices presents a unique opportunity to explore transient\u0000superconductivity on top of a correlated false vacuum. Specifically, we\u0000consider superconductors which are terminated by an apparent first-order phase\u0000transition to a correlated phase with different symmetry. We propose that\u0000quenching across this transition leads to a non-equilibrium ephemeral\u0000superconductor, readily detectable using straightforward transport\u0000measurements. Besides enabling a simple detection scheme, the transient\u0000superconductor also generically enhances the false vacuum lifetime, potentially\u0000by orders of magnitude. In several scenarios, the complimentary effect takes\u0000place as well: superconductivity is temporarily emboldened in the false vacuum,\u0000albeit ultimately decaying. We demonstrate the applicability of these claims\u0000for two different instances of superconductivity terminated by a first order\u0000transition in rhombohedral graphene. The obtained decay timescales position\u0000this class of materials as a promising playground to unambiguously realize and\u0000measure non-equilibrium superconductivity.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142210235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Accelerated Lanthanide Intercalation into Graphite Catalyzed by Na 在 Na 催化下加速镧系元素与石墨的互钙化

arXiv - PHYS - Superconductivity Pub Date : 2024-09-03 DOI: arxiv-2409.01624

Akira Iyo, Hiroshi Fujihisa, Yoshito Gotoh, Shigeyuki Ishida, Hiroshi Eisaki, Hiraku Ogino, Kenji Kawashima

引用次数: 0

Analysis of Thermal Grooving Effects on Vortex Penetration in Vapor-Diffused Nb3Sn 蒸汽扩散 Nb3Sn 中涡流穿透的热开槽效应分析

arXiv - PHYS - Superconductivity Pub Date : 2024-09-03 DOI: arxiv-2409.01569

Eric M. Lechner, Olga Trofimova, Jonathan W. Angle, Madison C. DiGuilio, Uttar Pudasaini

引用次数: 0

Pairing transitions in a Binary Bose Gas 二元玻色气体中的配对转换

arXiv - PHYS - Superconductivity Pub Date : 2024-09-03 DOI: arxiv-2409.01565

Zesheng Shen, Lan Yin

引用次数: 0

Field-free superconducting diode effect in layered superconductor FeSe 层状超导体 FeSe 中的无场超导二极管效应

arXiv - PHYS - Superconductivity Pub Date : 2024-09-03 DOI: arxiv-2409.01715

Utane NagataDep. Electronic Science and Engineering, Kyoto Univ, Motomi AokiDep. Electronic Science and Engineering, Kyoto UnivCSRN-Kyoto, Akito DaidoGraduate School of Science, Kyoto Univ, Shigeru KasaharaOkayama Univ, Yuichi KasaharaGraduate School of Science, Kyoto Univ, Ryo OhshimaDep. Electronic Science and Engineering, Kyoto UnivCSRN-Kyoto, Yuichiro AndoDep. Electronic Science and Engineering, Kyoto UnivCSRN-Kyoto, Youichi YanaseCSRN-KyotoGraduate School of Science, Kyoto Univ, Yuji MatsudaGraduate School of Science, Kyoto Univ, Masashi ShiraishiDep. Electronic Science and Engineering, Kyoto UnivCSRN-Kyoto

{"title":"Field-free superconducting diode effect in layered superconductor FeSe","authors":"Utane NagataDep. Electronic Science and Engineering, Kyoto Univ, Motomi AokiDep. Electronic Science and Engineering, Kyoto UnivCSRN-Kyoto, Akito DaidoGraduate School of Science, Kyoto Univ, Shigeru KasaharaOkayama Univ, Yuichi KasaharaGraduate School of Science, Kyoto Univ, Ryo OhshimaDep. Electronic Science and Engineering, Kyoto UnivCSRN-Kyoto, Yuichiro AndoDep. Electronic Science and Engineering, Kyoto UnivCSRN-Kyoto, Youichi YanaseCSRN-KyotoGraduate School of Science, Kyoto Univ, Yuji MatsudaGraduate School of Science, Kyoto Univ, Masashi ShiraishiDep. Electronic Science and Engineering, Kyoto UnivCSRN-Kyoto","doi":"arxiv-2409.01715","DOIUrl":"https://doi.org/arxiv-2409.01715","url":null,"abstract":"The superconducting diode effect (SDE), where zero-resistance states appear\u0000nonreciprocally during current injection, is receiving tremendous interest in\u0000both fundamental and applied physics because the SDE is a novel manifestation\u0000of symmetry breaking and enables the creation of a novel diode without energy\u0000loss. In particular, magnetic-field-free SDEs have been extensively\u0000investigated because of their potential to serve as building blocks for\u0000superconducting circuit technology. In this letter, we report the field-free\u0000SDE in a layered superconductor, FeSe. Its underlying physics is clarified by\u0000systematic controlled experiments to be an interplay of a large thermoelectric\u0000response and geometrical asymmetry in FeSe. Our findings can pave a new avenue\u0000for the construction of novel material and device platforms utilizing SDEs.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142210018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impurity States in Altermagnetic Superconductors 异磁超导体中的杂质状态

arXiv - PHYS - Superconductivity Pub Date : 2024-09-02 DOI: arxiv-2409.01008

Andrea Maiani, Rubén Seoane Souto

{"title":"Impurity States in Altermagnetic Superconductors","authors":"Andrea Maiani, Rubén Seoane Souto","doi":"arxiv-2409.01008","DOIUrl":"https://doi.org/arxiv-2409.01008","url":null,"abstract":"Altermagnetic superconductors hold the potential for novel phenomena,\u0000including topological states, finite-momentum superconductivity, as well as\u0000promising applications in spintronics. However, an experimental demonstration\u0000of the coexistence of these two effects is still lacking. In this work, we\u0000propose potential impurities as a way to probe the distinctive properties of\u0000altermagnetic superconductors. These impurities induce spin-polarized subgap\u0000states that extend along the crystal axes, inheriting the magnetic\u0000characteristics of the bulk. When the impurities respect the bulk symmetries,\u0000they generate spin-degenerate doublets; otherwise, the degeneracy is lifted. An\u0000external magnetic field aligned with the N'eel vector can tune the energies of\u0000the spin components of the subgap states. These components show different\u0000spatial extensions that can be measured via local probes, like scanning\u0000tunneling microscopy. For certain parameters, the impurity state can induce a\u0000local sign change on the order parameter, so-called $pi$-transition. Lastly,\u0000we investigate the interaction between impurities, revealing a\u0000position-dependent effective coupling that facilitates the engineering of\u0000spin-dependent tunneling. This tunable coupling introduces a new approach for\u0000in-situ control of devices critical for quantum information processing and\u0000topological superconductivity.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142210009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Universal degradation of high-temperature superconductors due to impurity scattering: predicting the performance loss in fusion magnets 杂质散射导致的高温超导体普遍退化：预测聚变磁体的性能损失

arXiv - PHYS - Superconductivity Pub Date : 2024-09-02 DOI: arxiv-2409.01376

M. Eisterer, A. Bodenseher, R. Unterrainer

引用次数: 0

Directly visualizing nematic superconductivity driven by the pair density wave in NbSe$_2$ 直接可视化 NbSe$_2$ 中由对密度波驱动的向列超导性

arXiv - PHYS - Superconductivity Pub Date : 2024-09-01 DOI: arxiv-2409.00660

Lu Cao, Yucheng Xue, Yingbo Wang, Fu-Chun Zhang, Jian Kang, Hong-Jun Gao, Jinhai Mao, Yuhang Jiang

{"title":"Directly visualizing nematic superconductivity driven by the pair density wave in NbSe$_2$","authors":"Lu Cao, Yucheng Xue, Yingbo Wang, Fu-Chun Zhang, Jian Kang, Hong-Jun Gao, Jinhai Mao, Yuhang Jiang","doi":"arxiv-2409.00660","DOIUrl":"https://doi.org/arxiv-2409.00660","url":null,"abstract":"Pair density wave (PDW) is a distinct superconducting state characterized by\u0000a periodic modulation of its order parameter in real space. Its intricate\u0000interplay with the charge density wave (CDW) state is a continuing topic of\u0000interest in condensed matter physics. While PDW states have been discovered in\u0000cuprates and other unconventional superconductors, the understanding of diverse\u0000PDWs and their interactions with different types of CDWs remains limited. Here,\u0000utilizing scanning tunneling microscopy, we unveil the subtle correlations\u0000between PDW ground states and two distinct CDW phases -- namely,\u0000anion-centered-CDW (AC-CDW) and hollow-centered-CDW (HC-CDW) -- in 2H-NbSe$_2$.\u0000In both CDW regions, we observe coexisting PDWs with a commensurate structure\u0000that aligns with the underlying CDW phase. The superconducting gap size,\u0000$Delta(r)$, related to the pairing order parameter is in phase with the charge\u0000density in both CDW regions. Meanwhile, the coherence peak height, $H(r)$,\u0000qualitatively reflecting the electron-pair density, exhibits a phase difference\u0000of approximately $2pi/3$ relative to the CDW. The three-fold rotational\u0000symmetry is preserved in the HC-CDW region but is spontaneously broken in the\u0000AC-CDW region due to the PDW state, leading to the emergence of nematic\u0000superconductivity.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142210011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0