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Related papers: Impurity-assisted Andreev reflection at a spin-act…

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We present a theory of Andreev reflection in a ferromagnet/superconductor/ferromagnet double junction system. The spin polarized quasiparticles penetrate to the superconductor in the range of penetration depth from the interface by the…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Taro Yamashita , Hiroshi Imamura , Saburo Takahashi , Sadamichi Maekawa

Crossed Andreev reflections and cotunneling occur between two neighbouring superconductor- normal metal or superconducting-ferromagnet interfaces. Previous works assumed a clean BCS superconductor. Here the calculation of the corresponding…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 D. Feinberg

We show that Andreev reflection in a junction between ferromagnetic (F) and superconducting (S) graphene regions is fundamentally different from the common FS junctions. For a weakly doped F graphene with an exchange field $h$ larger than…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Malek Zareyan , Hakimeh Mohammadpour , Ali G. Moghaddam

We analyze the charge transport between a one-dimensional weakly interacting electron gas and a superconductor within the scaling approach in the basis of scattering states. We derive the renormalization group equations, which fully account…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 M. Titov , M. Mueller , W. Belzig

Our previous point-contact Andreev reflection studies of the heavy-fermion superconductor CeCoIn$_5$ using Au tips have shown two clear features: reduced Andreev signal and asymmetric background conductance [1]. To explore their physical…

The Andreev Reflection is the key mechanism for the superconducting proximity effect. It provides phase correlations in a system of non-interacting electrons at mesoscopic scales, i.e. over distances much larger than the microscopic lengths…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 B. Pannetier , H. Courtois

We present a description of spin-polarized transport in mesoscopic ferromagnet-superconductor (F/S) systems, where the transport is diffusive, and the interfaces are transparent. It is shown that the spin reversal associated with Andreev…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 F. J. Jedema , B. J. van Wees , B. H. Hoving , A. T. Filip , T. M. Klapwijk

We consider Andreev reflection in a two dimensional junction between a normal metal and a heavy fermion superconductor in the Fulde-Ferrell (FF) type of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state. We assume s-wave symmetry of the…

Superconductivity · Physics 2011-03-10 J. Kaczmarczyk , M. Sadzikowski , J. Spałek

The Josephson current in S-F-S junctions is described by taking into account different reflection (transmission) amplitudes for quasiparticles with spin up and down. We show that the 0-$\pi$ transition in the junctions can take place at…

Mesoscale and Nanoscale Physics · Physics 2016-08-31 Yu. S. Barash , I. V. Bobkova

Complete suppression of the native n-type Schottky barrier is demonstrated in Al/InGaAs(001) junctions grown by molecular-beam-epitaxy. This result was achieved by the insertion of Si bilayers at the metal-semiconductor interface allowing…

Superconductivity · Physics 2007-05-23 S. De Franceschi , F. Giazotto , F. Beltram , L. Sorba , M. Lazzarino , A. Franciosi

At a normal-metal/superconductor interface, an incident electron from the normal-metal (N) side can be normally reflected as an electron or Andreev reflected as a hole. We show that pronounced lateral shifts along the interface between the…

Mesoscale and Nanoscale Physics · Physics 2018-09-12 Ying Liu , Zhi-Ming Yu , Hua Jiang , Shengyuan A. Yang

We study clean, edge-contacted graphene/superconductor interfaces in both the quantum Hall (QH) and zero field regimes. We find that Andreev reflection is substantially stronger than at an interface with a semiconductor two-dimensional…

Mesoscale and Nanoscale Physics · Physics 2025-06-30 Alexey Bondarev , Gu Zhang , Harold U. Baranger

Josephson junctions (JJs), where both time-reversal and inversion symmetry are broken, exhibit a phase shift $\phi_0$ in their current-phase relation. This allows for an anomalous supercurrent to flow in the junction even in the absence of…

Superconductivity · Physics 2022-01-11 Alberto Hijano , Stefan Ilić , F. Sebastián Bergeret

Superconducting proximity junctions made of topological insulator (TI) nanoribbons (NRs) provide a useful platform for studying topological superconductivity. We report on the fabrication and measurement of Josephson junctions (JJs) using…

Mesoscale and Nanoscale Physics · Physics 2022-01-05 Rak-Hee Kim , Nam-Hee Kim , Bongkeon Kim , Yasen Hou , Dong Yu , Yong-Joo Doh

We study narrow ballistic Josephson weak links in a InAs quantum wells contacted by Nb electrodes and find a dramatic magnetic-field suppression of the Andreev reflection amplitude, which occurs even for in-plane field orientation with…

Mesoscale and Nanoscale Physics · Physics 2010-01-04 F. Rohlfing , G. Tkachov , F. Otto , K. Richter , D. Weiss , G. Borghs , C. Strunk

We consider Andreev reflection in ferromagnet-superconductor junctions and extend the treatment by de Jong and Beenakker to incorporate the effect of a repulsive potential at the interface. We show the existence of a spin accumulation at a…

Superconductivity · Physics 2007-05-23 R. Mélin , O. Bourgeois

Using the time-dependent density-matrix renormalization group (tDMRG), we study the time evolution of electron wave packets in one-dimensional (1D) metal-superconductor heterostructures. The results show Andreev reflection at the interface,…

Strongly Correlated Electrons · Physics 2015-02-11 K. A. Al-Hassanieh , Julian Rincon , G. Alvarez , E. Dagotto

Andreev reflection at the interface between a ferromagnet and a superconductor has become a foundation of a versatile new technique of measuring the spin polarization of magnetic materials. In this paper we will briefly outline a general…

Materials Science · Physics 2009-10-31 I. I. Mazin , A. A. Golubov , B. Nadgorny

Using a generalization of the non-crossing approximation which incorporates Andreev reflection, we study the properties of an infinite-U Anderson impurity coupled to two superconducting leads. In the regime where $\Delta$ and $T_K$ are…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Aashish A. Clerk , Vinay Ambegaokar

We report the study of ballistic transport in normal metal/graphene/superconductor junctions in edge-contact geometry. While in the normal state, we have observed Fabry-P\'{e}rot resonances suggesting that charge carriers travel…

Mesoscale and Nanoscale Physics · Physics 2019-10-30 P. Pandey , R. Kraft , R. Krupke , D. Beckmann , R. Danneau