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Related papers: Specular Interband Andreev Reflections in Graphene

200 papers

Graphene's exceptional electronic mobility, gate-tunability, and contact transparency with superconducting materials make it ideal for exploring the superconducting proximity effect. However, the work function difference between graphene…

Mesoscale and Nanoscale Physics · Physics 2025-03-18 Seong Jang , Geon-Hyoung Park , Sein Park , Hyeon-Woo Jeong , Kenji Watanabe , Takashi Taniguchi , Gil-Ho Lee

The electron-hole conversion at the normal-metal superconductor interface in inversion-symmetric Weyl semimetals is investigated with an effective two-band model. We find that the specular Andreev reflection of Weyl fermions has two unusual…

Superconductivity · Physics 2015-06-15 Wei Chen , Liang Jiang , R. Shen , L. Sheng , B. G. Wang , D. Y. Xing

Novel fermions with a pseudospin-1 structure can be realized as emergent quasiparticles in condensed matter systems. Here, we investigate its unusual properties during the Andreev reflection at a normal-metal/superconductor (NS) interface.…

Mesoscale and Nanoscale Physics · Physics 2020-07-01 Xiaolong Feng , Ying Liu , Zhi-Ming Yu , Zhongshui Ma , L. K. Ang , Yee Sin Ang , Shengyuan A. Yang

The Andreev reflection of narrow ferromagnet/superconductor point contacts is theoretically studied. We show that the conductance quantization depends on whether the contact region is superconducting or ferromagnetic as well as on the…

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

Andreev reflection in graphene is special since it can be of two types- retro or specular. Specular Andreev reflection (SAR) dominates when the position of the Fermi energy in graphene is comparable to or smaller than the superconducting…

Mesoscale and Nanoscale Physics · Physics 2018-08-07 Abhiram Soori , Manas Ranjan Sahu , Anindya Das , Subroto Mukerjee

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

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

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

We study the reflection of electrons and quasiparticles on point-contact interfaces between fractional quantum Hall (FQH) states and normal metals (leads), as well as interfaces between two FQH states with mismatched filling fractions. We…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 Nancy P. Sandler , Claudio de C. Chamon , Eduardo Fradkin

We have studied the interplay of Andreev reflection and cyclotron motion of quasiparticles at a superconductor-normal-metal interface with a strong magnetic field applied parallel to the interface. Bound states are formed due to the…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 H. Hoppe , U. Zuelicke , Gerd Schoen

We investigate the Andreev reflection and Josephson effect in the $\alpha$-T3 lattice which falls between graphene ($\alpha = 0$) and the dice lattice ($\alpha = 1$) by adjusting the parameter $\alpha$. In the regime of specular Andreev…

Mesoscale and Nanoscale Physics · Physics 2021-10-04 Xingfei Zhou

A graphene sheet partially covered with a bulk superconductor serves as a normal conductor--superconductor (NS) junction, in which electron transport is mainly governed by Andreev reflection (AR). As excess carriers induced over the covered…

Mesoscale and Nanoscale Physics · Physics 2017-06-28 Yositake Takane , Katsuhide Yarimizu , Akinobu Kanda

We calculate the density of states of electron-hole excitations in a superconductor/normal-metal/superconductor (SNS) junction in graphene, in the long-junction regime that the superconducting gap is much larger than the Thouless energy. If…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 M. Titov , A. Ossipov , C. W. J. Beenakker

We study Andreev reflection in normal metal-superconductor junctions by using an extended Blonder-Tinkham-Klapwijk model combined with transport calculations based on density functional theory. Starting from a parameter-free description of…

Mesoscale and Nanoscale Physics · Physics 2014-10-28 Awadhesh Narayan , Ivan Rungger , Stefano Sanvito

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

We investigate the Andreev reflection in a normal metal/charge-4e superconductor junction.Compare with the electron-hole conversion in normal charge-2e superconductors, here four electrons participate simultaneously, enriching the…

Superconductivity · Physics 2024-10-30 Yi-Xin Dai , Qing-Feng Sun

Dynamic conductance spectra are taken from Au/CeCoIn$_5$ point contacts in the Sharvin limit along the (001) and (110) directions. Our conductance spectra, reproducibly obtained over wide ranges of temperature, constitute the cleanest data…

Superconductivity · Physics 2015-06-25 Wan Kyu Park , Laura H. Greene , John L. Sarrao , Joe D. Thompson

We report on Andreev reflections at clean NbSe2-bilayer graphene junctions. The high transparency of the junction, which manifests as a large conductance enhancement of up to 1.8, enables us to see clear evidence of a proximity-induced…

Mesoscale and Nanoscale Physics · Physics 2020-05-06 Jing Li , Han-Bing Leng , Hailong Fu , Kenji Watanabe , Takashi Taniguchi , Xin Liu , Chao-Xing Liu , Jun Zhu

A recently developed theory for the problem of Andreev reflection between a normal metal (N) and a multiband superconductor (MBS) assumes that the incident wave from the normal metal is coherently transmitted through several bands inside…

Superconductivity · Physics 2015-05-14 M. A. N. Araujo , P. D. Sacramento

The problem of Andreev reflection between a normal metal and a multiband superconductor is addressed. The appropriate matching conditions for the wave function at the interface are established on the basis of an extension of quantum…

Superconductivity · Physics 2009-05-29 M. A. N. Araujo , P. D. Sacramento