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Related papers: Anomalous conductances in an ultracold quantum wir…

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Short length quantum wires (quantum contacts) exhibit a conductance structure at the value of conductance close to 0.7 \times 2e^2/h. The structure is also called the conductance anomaly. In longer contacts the structure evolves to the…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 O. P. Sushkov

We report an unusual insulating state in one-dimensional quantum wires with a non-uniform confinement potential. The wires consist of a series of closely spaced split gates in high mobility GaAs/AlGaAs heterostructures. At certain…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 KJ Thomas , DL Sawkey , M Pepper , WR Tribe , I Farrer , MY Simmons , DA Ritchie

We investigate thermomagnetic transport in an ultracold atomic system with two ferromagnets linked via a magnetic quantum point contact. Using nonequilibrium Green's function approach, we show a divergence in spin conductance and a slowing…

Quantum Gases · Physics 2024-10-18 Yuta Sekino , Yuya Ominato , Hiroyuki Tajima , Shun Uchino , Mamoru Matsuo

In a recent publication, Lee $et$ $al.$ discussed experimental observation of Klein tunneling into a proximity-induced topological superconducting state of SmB$_{6}$ through the measurement of Andreev reflection with low-bias conductance…

Superconductivity · Physics 2019-07-18 Shekhar Das , Kurt Gloos , Yu. G. Naidyuk , Goutam Sheet

We investigate a normal metal -- superconductor (point) contact in the limit where the number of conducting channels in the metallic wire is reduced to few channels. As the effective Fermi energy drops below the gap energy, a conducting…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Gordey B. Lesovik , Gianni Blatter

We consider a weakly interacting finite wire with short and long range interactions. The long range interactions enhance the $4k_{F}$ scattering and renormalize the wire to a strongly interacting limit. For large screening lengths, the…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 D. Schmeltzer , A. Kuklov , M. Malard

The conventional description of transport through the interface between a normal conductor and a superconductor reduces the system to a one-dimensional problem treating Andreev reflection based on a zero-dimensional Sharvin type…

We experimentally study electron transport across a single planar junction between the indium electrode and MnTe altermagnet candidate. We confirm standard Ohmic behavior with strictly linear current-voltage curves above the indium critical…

Mesoscale and Nanoscale Physics · Physics 2024-10-17 D. Yu. Kazmin , V. D. Esin , Yu. S. Barash , A. V. Timonina , N. N. Kolesnikov , E. V. Deviatov

We experimentally investigate transport properties of a single planar junction between the niobium superconductor and the edge of a two-dimensional electron system in a narrow $In_{0.75}Ga_{0.25}As$ quantum well with strong Rashba-type…

Mesoscale and Nanoscale Physics · Physics 2018-01-30 A. Kononov , G. Biasiol , L. Sorba , E. V. Deviatov

We demonstrate several new electron transport phenomena mediated by Andreev bound states (ABSs) that form on three-terminal carbon nanotube (CNT) QDs, with one superconducting (S) contact in the center and two adjacent normal metal (N)…

Mesoscale and Nanoscale Physics · Physics 2017-11-10 J. Gramich , A. Baumgartner , C. Schönenberger

Resonant Andreev reflection through superconductor-carbon-nanotube devices was investigated theoretically with a focus on the superconducting proximity effect. Consistent with a recent experiment, we find that for high transparency devices…

Condensed Matter · Physics 2009-11-07 Yadong Wei , Jian Wang , Hong Guo , Hatem Mehrez , R. Roland

Thermoelectric transport coefficients are determined for semiconductor quantum wires with weak thickness fluctuations. Such systems exhibit anomalies in conductance near 1/4 and 3/4 of 2e^2/h on the rising edge to the first conductance…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 T. Rejec , A. Ramsak , J. H. Jefferson

The influence of phase shifts of electron waves passing through and reflected by the potential barrier on the Andreev reflection in a ferromagnet/isolator/d-wave superconductor (FIS) contact is studied. It is found that in a superconductor…

Superconductivity · Physics 2009-01-13 B. P. Vodopyanov

We discuss the mechanisms of unconventional superconductivity and superfluidity in 3D and 2D fermionic systems with purely repulsive interaction at low densities. We construct phase diagrams of these systems and find the areas of the…

Superconductivity · Physics 2015-11-13 M. Yu. Kagan , V. A. Mitskan , M. M. Korovushkin

Electron correlation in a quantum many-body state appears as peculiar scattering behaviour at its boundary, symbolic of which is Andreev reflection at a metal-superconductor interface. Despite being fundamental in nature, dictated by the…

Mesoscale and Nanoscale Physics · Physics 2021-05-20 Masayuki Hashisaka , Thibaut Jonckheere , Takafumi Akiho , Satoshi Sasaki , Jerome Rech , Thierry Martin , Koji Muraki

For unpolarized electrons in a clean quantum wire, density functional theory reveals a thermally activated suppression of conductance. The activation temperature T_A grows slowly (roughly quadratically) with gate voltage due to pinning of…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Kenji Hirose , Ned S. Wingreen

In this work, we theoretically study transverse magnetic focusing in a two-dimensional electron gas with strong Rashba spin-orbit interaction when proximitized along its edge with a superconducting contact. The presence of superconducting…

Mesoscale and Nanoscale Physics · Physics 2021-10-05 Lucila Peralta Gavensky , Gonzalo Usaj , C. A. Balseiro

We calculate the conductance of a junction between a disordered superconductor and a very strong half-metallic ferromagnet admitting electrons with only one spin projection. A usual mechanism of Andreev reflection is strongly suppressed in…

Superconductivity · Physics 2024-01-29 M. E. Ismagambetov , P. M. Ostrovsky , M. V. Feigel'man

We evaluate the differential conductance measured in a scanning tunneling microscopy (STM) setting at arbitrary electron transmission between an STM tip and a two-dimensional (2D) superconductor with arbitrary gap structure. Our analytical…

Superconductivity · Physics 2023-05-30 P. O. Sukhachov , Felix von Oppen , L. I. Glazman

Sub-gap conductance at a large area junction with a rough interface of a ferromagnet and a high-T$_{C}$ superconductor is superimposed by multiple peaks which is not expected from an ideal point contact Andreev reflection process. We…

Superconductivity · Physics 2009-03-25 N. Ghosh , H. Schmidt , M. Grundmann