Anomalous Cooper pair interference on Bi2Te3 surface

It is believed that the edges of a chiral p-wave superconductor host Majorana modes, relating to a mysterious type of fermions predicted seven decades ago. Much attention has been paid to search for p-wave superconductivity in solid-state systems, including recently those with strong spin-orbit coup...

Full description

Saved in:
Bibliographic Details
Published in:arXiv.org 2013-08
Main Authors: Shen, Jie, Ding, Yue, Pang, Yuan, Yang, Fan, Qu, Fanming, Ji, Zhongqing, Xiunian Jing, Fan, Jie, Liu, Guangtong, Yang, Changli, Chen, Genghua, Lu, Li
Format: Article
Language:English
Subjects:
Bismuth tellurides
Cooper pairs
Fermions
Interference
Pattern recognition
Quantum mechanics
Quantum phenomena
Quantum theory
Spin-orbit interactions
Superconducting quantum interference devices
Superconductivity
Superconductors
Topological insulators
Topology
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:It is believed that the edges of a chiral p-wave superconductor host Majorana modes, relating to a mysterious type of fermions predicted seven decades ago. Much attention has been paid to search for p-wave superconductivity in solid-state systems, including recently those with strong spin-orbit coupling (SOC). However, smoking-gun experiments are still awaited. In this work, we have performed phase-sensitive measurements on particularly designed superconducting quantum interference devices constructing on the surface of topological insulators Bi2Te3, in such a way that a substantial portion of the interference loop is built on the proximity-effect-induced superconducting surface. Two types of Cooper interference patterns have been recognized at low temperatures. One is s-wave like and is contributed by a zero-phase loop inhabited in the bulk of Bi2Te3. The other, being identified to relate to the surface states, is anomalous for that there is a phase shift between the positive and negative bias current directions. The results support that the Cooper pairs on the surface of Bi2Te3 have a 2\pi Berry phase which makes the superconductivity p_x+ip_y-wave-like. Mesoscopic hybrid rings as constructed in this experiment are presumably arbitrary-phase loops good for studying topological quantum phenomena.
ISSN:2331-8422