Geometrical enhancement of the proximity effect in quantum wires with extended superconducting tunnel contacts
Giorgos Fagas, Grygoriy Tkachov, Andreas Pfund, Klaus Richter
DOI 10.1103/PhysRevB.71.224510 · Physical Review B
Active bibliographic source — not scientific approval
Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.
Abstract
We study Andreev reflection in a ballistic one-dimensional channel coupled in parallel to a superconductor via a tunnel barrier of finite length L. The dependence of the low-energy Andreev reflection probability RA on L reveals the existence of a characteristic length scale ξN beyond which RA(L) is enhanced up to unity despite the low interfacial transparency. The Andreev reflection enhancement is due to the strong mixing of particle and hole states that builds up in contacts exceeding the coherence length ξN, leading to a small energy gap (minigap) in the density of states of the normal system. The role of the geometry of such hybrid contacts is discussed in the context of the experimental observation of zero-bias Andreev anomalies in the resistance of extended carbon nanotube/superconductor junctions in field effect transistor setups.
Similar papers
Mesoscopic proximity effect probed through superconducting tunneling contacts
similarity 0.92Frank K. Wilhelm & Alexander A. Golubov
Source status unknown — claims are unverified
Hard gap in a normal layer coupled to a superconductor
similarity 0.91Christopher R. Reeg & Dmitrii L. Maslov
Source status unknown — claims are unverified
Andreev magnetotransport in low-dimensional proximity structures: Spin-dependent conductance enhancement
similarity 0.91Grygoriy Tkachov & Klaus Richter
Source status unknown — claims are unverified
Observation of Andreev Bound States at Spin-active Interfaces
similarity 0.91F. Hübler et al.
Source status unknown — claims are unverified
Geometrical effects on the downstream conductance in quantum-Hall–superconductor hybrid systems
similarity 0.91A. David et al.
Source status unknown — claims are unverified
Andreev reflection enhancement in semiconductor-superconductor structures
similarity 0.90Shlomi Bouscher et al.
Source status unknown — claims are unverified