English
Related papers

Related papers: Anomalous conductances in an ultracold quantum wir…

200 papers

We analyze in detail the superconductivity that arises in an extended Hubbard model describing a multiband system with repulsive interactions. We show that virtual interband processes induce an effective attractive interaction for small…

Superconductivity · Physics 2022-07-22 Valentin Crépel , Tommaso Cea , Liang Fu , Francisco Guinea

We show that noncollinear Andreev reflections can be induced at interfaces of semiconductor nanowires with spin-orbit coupling, Zeeman splitting and proximity-induced superconductivity. In a noncollinear local Andreev reflection, the spin…

Superconductivity · Physics 2014-11-27 B. H. Wu , W. Yi , J. C. Cao , G. -C. Guo

We present here an extensive theoretical analysis of the supercurrent of a superconducting point contact of arbitrary transparency in the presence of a microwave field. Our study is mainly based on two different approaches: a two-level…

Superconductivity · Physics 2015-05-28 F. S. Bergeret , P. Virtanen , A. Ozaeta , T. T. Heikkilä , J. C. Cuevas

Directional point-contact Andreev-reflection spectroscopy measurements on the Ba$_{0.55}$K$_{0.45}$Fe$_2$As$_2$ single crystals are presented. The spectra show significant differences when measured in the $ab$ plane in comparison with those…

Superconductivity · Physics 2009-11-13 P. Szabo , Z. Pribulova , G. Pristas , S. L. Bud'ko , P. C. Canfield , P. Samuely

We present a theoretical analysis of the recent experimental results of Thomas et al on transport properties of spin polarized quantum wires. We suggest an explanation of the observed deviations of the conductance from the universal value…

Strongly Correlated Electrons · Physics 2008-02-03 D. Schmeltzer , E. Kogan , R. Berkovits , M. Kaveh

We use point contact spectroscopy (PCS) to probe the superconducting properties of electron doped $\rm{Ba(Fe_{1-x}Co_x)_2As_2}$ ($\rm{x = 0.05, 0.055, 0.07, 0.08}$) and hole doped $\rm{Ba_{0.8}K_{0.2}Fe_2As_2}$. PCS directly probes the low…

Superconductivity · Physics 2013-07-09 H. Z. Arham , C. R. Hunt , J. Gillett , S. D. Das , S. E. Sebastian , D. Y. Chung , M. G. Kanatzidis , L. H. Greene

We construct a theory for low-energy quantum transport in normal$\mid$superconductor junctions involving the recently discovered iron-based high-$T_c$ superconductors. We properly take into account both Andreev bound surface states and the…

Superconductivity · Physics 2009-11-13 Jacob Linder , Asle Sudbø

With the aid of the Keldysh technique we develop a microscopic theory of non-local electron transport in three-terminal NSN structures consisting of a chaotic superconducting quantum dot attached to one superconducting and two normal…

Superconductivity · Physics 2009-07-06 D. S. Golubev , A. D. Zaikin

Electronic heat transport along the flux lines in a long ballistic mesoscopic superconductor cylinder with a radius of the order of several coherence lengths is investigated theoretically using both semiclassical approach and the full…

Recent electronic transport experiments using metallic contacts attached to proteins identified some 'stylized facts' which contradict conventional wisdom that increasing either the spatial distance between the electrodes or the temperature…

Disordered Systems and Neural Networks · Physics 2019-09-04 Eszter Papp , Dávid P. Jelenfi , Máté T. Veszeli , Gábor Vattay

Electron-electron (e-e) collisions can impact transport in a variety of surprising and sometimes counterintuitive ways. Despite strong interest, experiments on the subject proved challenging because of the simultaneous presence of different…

We study Andreev processes and nonlocal transport in a three-terminal graphene-superconductor hybrid system under a quantizing perpendicular magnetic field [G.-H. Lee et al., Nature Phys. 13, 693 (2017)]. We find that the amplitude of the…

Mesoscale and Nanoscale Physics · Physics 2018-05-16 Michael Beconcini , Marco Polini , Fabio Taddei

We report on high-resolution differential conductance experiments on nanoscale superconductor/ferromagnet tunnel junctions with ultra-thin oxide tunnel barriers. We observe subgap conductance features which are symmetric with respect to…

Mesoscale and Nanoscale Physics · Physics 2012-11-14 F. Hübler , M. J. Wolf , T. Scherer , D. Wang , D. Beckmann , H. v. Löhneysen

The low-temperature conductance (G) characteristics between a normal metal and a clean superconductor (S) carrying a supercurrent $I_s$ parallel to the interface is theoretically investigated. Increasing $I_s$ causes lowering and broadening…

Superconductivity · Physics 2009-11-10 Degang Zhang , C. S. Ting , C. -R. Hu

We investigate quantum transport through strongly disordered barriers, made of a material with exceptionally high resistivity that behaves as an Anderson insulator or a ``bad metal'' in the bulk, by analyzing the distribution of Landauer…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Branislav K. Nikolic , Ralitsa L. Dragomirova

Particle transport across Josephson junctions is commonly described using a simplifying approximation (often called the Andreev approximation), which assumes that excitations are fixed at the Fermi momentum and only Andreev reflections,…

Mesoscale and Nanoscale Physics · Physics 2022-11-09 F. Setiawan , Johannes Hofmann

Proximity-induced superconductivity in fractional quantum Hall edges is a prerequisite to proposed realizations of parafermion zero-modes. A recent experimental work [G\"{u}l et al., Phys. Rev. X 12, 021057 (2022)] provided evidence for…

Mesoscale and Nanoscale Physics · Physics 2023-04-18 Noam Schiller , Barak A. Katzir , Ady Stern , Erez Berg , Netanel H. Lindner , Yuval Oreg

Coherent charge transport along ballistic paths can be introduced into graphene by Andreev reflection, for which an electron reflects from a superconducting contact as a hole, while a Cooper pair is transmitted. We use a liquid-helium…

Mesoscale and Nanoscale Physics · Physics 2020-08-26 S. Bhandari , G. -H. Lee , K. Watanabe , T. Taniguchi , P. Kim , R. M. Westervelt

The electrical transport properties of corner-shaped Al superconducting microstrips have been investigated. We demonstrate that the sharp turns lead to asymmetric vortex dynamics, allowing for easier penetration from the inner concave angle…

The conductance in two-dimensional (2D) normal-superconducting (NS) systems is analyzed in the limit of strong magnetic fields when the transport is mediated by the electron-hole states bound to the sample edges and NS interface, i.e., in…

Superconductivity · Physics 2010-08-03 I. M. Khaymovich , N. M. Chtchelkatchev , I. A. Shereshevskii , A. S. Mel'nikov