arXiv - PHYS - Superconductivity最新文献

Identifying inflated Fermi surfaces via thermoelectric response in $d$-wave superconductor heterostructure 通过 d$ 波超导体异质结构中的热电响应识别膨胀费米面

arXiv - PHYS - Superconductivity Pub Date : 2024-09-18 DOI: arxiv-2409.12157

Amartya Pal, Paramita Dutta, Arijit Saha

{"title":"Identifying inflated Fermi surfaces via thermoelectric response in $d$-wave superconductor heterostructure","authors":"Amartya Pal, Paramita Dutta, Arijit Saha","doi":"arxiv-2409.12157","DOIUrl":"https://doi.org/arxiv-2409.12157","url":null,"abstract":"We theoretically investigate the thermoelectric response of inflated Fermi\u0000surfaces (IFSs) generated in a two dimensional unconventional $d$-wave\u0000superconductor subjected to an external in-plane Zeeman field. These IFSs\u0000exhibiting the same dimension as the underlying normal state Fermi surface are\u0000topologically protected by combinations of discrete symmetries. Utilizing the\u0000Blonder-Tinkham-Klapwijk formalism and considering normal-$d$-wave\u0000superconductor hybrid junction, we compute the thermoelectric coefficients\u0000including thermal conductance, Seebeck coefficient, figure of merit ($zT$), and\u0000examine the validation of Widemann-Franz law in the presence of both voltage\u0000and temperature bias. Importantly, as a signature of anisotropic nature of\u0000$d$-wave pairing, Andreev bound states (ABSs) formed at the\u0000normal-superconductor interface play a significant role in the thermoelectric\u0000response. In the presence of ABSs, we observe a substantial enhancement in\u0000Seebeck coefficient ($sim 200,mu$V/K) and $zT$ ($sim 3.5$) due to the\u0000generation of the IFSs and thus making such setup a potential candidate for\u0000device applications. Finally, we strengthen our continuum model results by\u0000computing the thermoelectric coefficients based on a lattice-regularized\u0000version of our continuum model.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253469","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

Spatially-resolved dynamics of the amplitude Schmid-Higgs mode in disordered superconductors 无序超导体中振幅施密德-希格斯模式的空间分辨动力学

arXiv - PHYS - Superconductivity Pub Date : 2024-09-18 DOI: arxiv-2409.11647

P. A. Nosov, E. S. Andriyakhina, I. S. Burmistrov

{"title":"Spatially-resolved dynamics of the amplitude Schmid-Higgs mode in disordered superconductors","authors":"P. A. Nosov, E. S. Andriyakhina, I. S. Burmistrov","doi":"arxiv-2409.11647","DOIUrl":"https://doi.org/arxiv-2409.11647","url":null,"abstract":"We investigate the spatially-resolved dynamics of the collective amplitude\u0000Schmid-Higgs (SH) mode in disordered Bardeen-Cooper-Schrieffer (BCS)\u0000superconductors and fermionic superfluids. We identify cases where the\u0000long-time SH response is determined by a pole in the averaged SH\u0000susceptibility, located on the unphysical sheet of its Riemann surface. Using\u0000analytic continuation across the two-particle branch cut, we obtain the\u0000zero-temperature dispersion relation and damping rate of the SH mode linked to\u0000this pole. When the coherence length significantly exceeds the mean free path,\u0000the pole is ``hidden'' behind the two-particle continuum edge at $2Delta$,\u0000leading to SH oscillations at late times decaying as $1/t^2$ with frequency\u0000$2Delta$. Nevertheless, the pole induces a peak in the retarded SH\u0000susceptibility at a frequency above $2Delta$ and causes sub-diffusive\u0000oscillations with a dynamical exponent $z=4$ at both late times and long\u0000distances. Conversely, long-distance oscillations at a fixed frequency $omega$\u0000occur only for $omega$ exceeding $2Delta$, with a spatial period diverging at\u0000the threshold as $1/(omega - 2Delta)^{1/4}$, up to logarithmic factors. When\u0000the coherence length is comparable to the mean free path, the pole can reemerge\u0000into the continuum, resulting in additional late-time oscillations at fixed\u0000wave vectors with frequencies above $2Delta$.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253508","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

Exploring functionalized Zr$_2$N and Sc$_2$N MXenes as superconducting candidates with $textit{ab initio}$ calculations 通过$textit{ab initio}$计算探索作为超导候选物质的官能化Zr$_2$N和Sc$_2$N MXenes

arXiv - PHYS - Superconductivity Pub Date : 2024-09-18 DOI: arxiv-2409.12052

Alpin N. Tatan, Osamu Sugino

引用次数: 0

Unconventional gate-induced superconductivity in transition-metal dichalcogenides 过渡金属二卤化物中的非常规栅极诱导超导电性

arXiv - PHYS - Superconductivity Pub Date : 2024-09-18 DOI: arxiv-2409.11834

Thibault Sohier, Marco Gibertini, Ivar Martin, Alberto F. Morpurgo

{"title":"Unconventional gate-induced superconductivity in transition-metal dichalcogenides","authors":"Thibault Sohier, Marco Gibertini, Ivar Martin, Alberto F. Morpurgo","doi":"arxiv-2409.11834","DOIUrl":"https://doi.org/arxiv-2409.11834","url":null,"abstract":"Superconductivity in few-layer semiconducting transition metal\u0000dichalcogenides (TMDs) can be induced by field-effect doping through\u0000ionic-liquid gating. While several experimental observations have been\u0000collected over the years, a fully-consistent theoretical picture is still\u0000missing. Here we develop a realistic framework that combines the predictive\u0000power of first-principles simulations with the versatility and insight of\u0000Bardeen-Cooper-Schrieffer gap equations to rationalize such experiments. The\u0000multi-valley nature of semiconducting TMDs in taken into account, together with\u0000the doping- and momentum-dependent electron-phonon and Coulomb interactions.\u0000Consistently with experiments, we find that superconductivity occurs when the\u0000electron density is large enough that the Q valleys get occupied, as a result\u0000of a large enhancement of electron-phonon interactions. Despite being\u0000phonon-driven, the superconducting state is predicted to be sensitive to\u0000Coulomb interactions, which can lead to the appearance of a relative sign\u0000difference between valleys and thus to a $s_{+-}$ character. We discuss\u0000qualitatively how such scenario may account for many of the observed physical\u0000phenomena for which no microscopic explanation has been found so far, including\u0000in particular the presence of a large subgap density of states, and the\u0000sample-dependent dome-shaped dependence of $T_c$ on accumulated electron\u0000density. Our results provide a comprehensive analysis of gate-induced\u0000superconductivity in semiconducting TMDs, and introduce an approach that will\u0000likely be valuable for other multivalley electronic systems, in which\u0000superconductivity occurs at relatively low electron density.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253503","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

Nuclear Spin-Lattice Relaxation Rate in Odd-Frequency Superconductivity 奇频超导中的核自旋-晶格弛豫率

arXiv - PHYS - Superconductivity Pub Date : 2024-09-17 DOI: arxiv-2409.10894

Shumpei Iwasaki, Yoji Ohashi

{"title":"Nuclear Spin-Lattice Relaxation Rate in Odd-Frequency Superconductivity","authors":"Shumpei Iwasaki, Yoji Ohashi","doi":"arxiv-2409.10894","DOIUrl":"https://doi.org/arxiv-2409.10894","url":null,"abstract":"We theoretically investigate the temperature dependence of nuclear\u0000spin-lattice relaxation rate $T_1^{-1}$ in bulk odd-frequency\u0000superconductivity. For a model odd-frequency pairing interaction, we first\u0000evaluate the superconducting order parameter, within the framework of the\u0000combined path-integral formalism with the saddle-point approximation. We then\u0000calculate $T_1^{-1}$ below the superconducting phase transition temperature\u0000$T_{rm c}$, to see how the odd-frequency pairing affects this physical\u0000quantity. In the odd-frequency $p$-wave state, while the so-called coherence\u0000peak is suppressed as in the even-frequency $p$-wave case, $T_1^{-1}$ is found\u0000to exhibit the Korringa-law-like behavior ($T_1^{-1}propto T$) except just\u0000below $T_{rm c}$, even without impurity scatterings. In the odd-frequency\u0000$s$-wave case, the behavior of $T_{1}^{-1}$ is found to be sensitive to the\u0000detailed spin structure of the superconducting order parameter: In a case,\u0000$T_1^{-1}$ is enhanced far below $T_{rm c}$, being in contrast to the\u0000conventional (even-frequency) $s$-wave BCS case, where the coherence peak\u0000appears just below $T_{rm c}$. We also show that the calculated $T_1^{-1}$ in\u0000the odd-frequency $p$-wave case well explains the recent experiment on\u0000CeRh$_{0.5}$Ir$_{0.5}$In$_5$, where the possibility of odd-frequency $p$-wave\u0000superconductivity was recently suggested experimentally.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253506","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

Quantum Geometric Effects on the Higgs Mode in Flat-band Superconductors 平带超导体中希格斯模式的量子几何效应

arXiv - PHYS - Superconductivity Pub Date : 2024-09-17 DOI: arxiv-2409.10891

Yuhang Xiao, Ning Hao

{"title":"Quantum Geometric Effects on the Higgs Mode in Flat-band Superconductors","authors":"Yuhang Xiao, Ning Hao","doi":"arxiv-2409.10891","DOIUrl":"https://doi.org/arxiv-2409.10891","url":null,"abstract":"Flat-band systems are of great interest due to their strong electron\u0000correlations and unique band geometry. Recent studies have linked the\u0000properties of Cooper pairs in flat-band superconductors to the quantum metric.\u0000Unlike prior studies primarily focused on quasiparticle fluctuations, in this\u0000work, we investigate quantum geometric effects on a collective mode of the\u0000order parameter-the Higgs mode. We derive the quantum goemetric Higgs-mode\u0000correlation length and investigate whether the nonlinear electromagnetic\u0000response of the Higgs mode persists in flat band. It turns out that the quantum\u0000metric will replaces energy derivatives, playing a crucial role in\u0000third-harmonic generation(THG). We further numerically calculated the\u0000correlation length and THG in the Lieb lattice. In contrast to traditional\u0000single-band results, Higgs mode fluctuations contribute almost entirely to THG,\u0000with the quasiparticle contribution being negligible. This finding provides\u0000valuable guidance for detecting Higgs modes in flat-band systems through\u0000optical methods and reveals the profound influence of quantum geometry in\u0000flat-band systems.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253505","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

Time-Reversal Symmetry Breaking in Re-Based Kagome Lattice Superconductor 再基鹿角晶格超导体中的时间逆转对称破缺

arXiv - PHYS - Superconductivity Pub Date : 2024-09-17 DOI: arxiv-2409.10941

Manasi Mandal, A. Kataria, P. K. Meena, R. K. Kushwaha, D. Singh, P. K. Biswas, R. Stewart, A. D. Hillier, R. P. Singh

引用次数: 0

Revealing the Origin and Nature of the Buried Metal-Substrate Interface Layer in Ta/Sapphire Superconducting Films 揭示钽/蓝宝石超导薄膜中埋藏的金属-基底界面层的起源和性质

arXiv - PHYS - Superconductivity Pub Date : 2024-09-16 DOI: arxiv-2409.10780

Aswin kumar Anbalagan, Rebecca Cummings, Chenyu Zhou, Junsik Mun, Vesna Stanic, Jean Jordan-Sweet, Juntao Yao, Kim Kisslinger, Conan Weiland, Dmytro Nykypanchuk, Steven L. Hulbert, Qiang Li, Yimei Zhu, Mingzhao Liu, Peter V. Sushko, Andrew L. Walter, Andi M. Barbour

{"title":"Revealing the Origin and Nature of the Buried Metal-Substrate Interface Layer in Ta/Sapphire Superconducting Films","authors":"Aswin kumar Anbalagan, Rebecca Cummings, Chenyu Zhou, Junsik Mun, Vesna Stanic, Jean Jordan-Sweet, Juntao Yao, Kim Kisslinger, Conan Weiland, Dmytro Nykypanchuk, Steven L. Hulbert, Qiang Li, Yimei Zhu, Mingzhao Liu, Peter V. Sushko, Andrew L. Walter, Andi M. Barbour","doi":"arxiv-2409.10780","DOIUrl":"https://doi.org/arxiv-2409.10780","url":null,"abstract":"Despite constituting a smaller fraction of the qubits electromagnetic mode,\u0000surfaces and interfaces can exert significant influence as sources of high-loss\u0000tangents, which brings forward the need to reveal properties of these extended\u0000defects and identify routes to their control. Here, we examine the structure\u0000and composition of the metal-substrate interfacial layer that exists in\u0000Ta/sapphire-based superconducting films. Synchrotron-based X-ray reflectivity\u0000measurements of Ta films, commonly used in these qubits, reveal an unexplored\u0000interface layer at the metal-substrate interface. Scanning transmission\u0000electron microscopy and core-level electron energy loss spectroscopy identified\u0000an approximately 0.65 text{nm} pm 0.05 text{nm} thick intermixing layer\u0000at the metal-substrate interface containing Al, O, and Ta atoms. Density\u0000functional theory (DFT) modeling reveals that the structure and properties of\u0000the Ta/sapphire heterojunctions are determined by the oxygen content on the\u0000sapphire surface prior to Ta deposition, as discussed for the limiting cases of\u0000Ta films on the O-rich versus Al-rich Al2O3 (0001) surface. By using a\u0000multimodal approach, integrating various material characterization techniques\u0000and DFT modeling, we have gained deeper insights into the interface layer\u0000between the metal and substrate. This intermixing at the metal-substrate\u0000interface influences their thermodynamic stability and electronic behavior,\u0000which may affect qubit performance.","PeriodicalId":501069,"journal":{"name":"arXiv - PHYS - Superconductivity","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253507","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 diodes induced by the loop current states 环流状态诱导的约瑟夫森二极管

arXiv - PHYS - Superconductivity Pub Date : 2024-09-16 DOI: arxiv-2409.09938

Qi-Kai Shen, Yi Zhang

引用次数: 0

Bound states and scattering of magnons on a superconducting vortex in ferromagnet-superconductor heterostructures 铁磁体-超导体异质结构中超导涡旋上的束缚态和磁子散射

arXiv - PHYS - Superconductivity Pub Date : 2024-09-16 DOI: arxiv-2409.10220

D. S. Katkov, S. S. Apostoloff, I. S. Burmistrov

引用次数: 0