Impurity effects on superconductivity on surfaces of topological insulators

Yuto Ito, Youhei Yamaji, Masatoshi Imada

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

A two-dimensional superconductor (SC) on surfaces of topological insulators (TIs) is a mixture of s-wave and helical p-wave components when induced by s-wave interactions, since spin and momentum are correlated. On the basis of the Abrikosov-Gor'kov theory, we reveal that unconventional SCs on the surfaces of TIs are stable against time-reversal symmetric (TRS) impurities within a region of small impurity concentration. Moreover, we analyze the stability of the SC on the surfaces of TIs against impurities beyond the perturbation theory by solving the real-space Bogoliubov- de Gennes equation for an effective tight-binding model of a TI. We find that the SC is stable against strong TRS impurities. The behaviors of bound states around an impurity suggest that the SC on the surfaces of TIs is not a topological SC.

Original languageEnglish
Article number084707
JournalJournal of the Physical Society of Japan
Volume81
Issue number8
DOIs
Publication statusPublished - 2012 Aug 1
Externally publishedYes

Fingerprint

superconductivity
insulators
impurities
wave interaction
perturbation theory
momentum

Keywords

  • Abrikosov-Gor'kov theory
  • Bogoliubov-de Gennes equation
  • Helical Dirac electron
  • Impurity induced state
  • Impurity scattering
  • Spin orbit interaction
  • Time reversal symmetry
  • Topological insulator
  • Unconventional superconductivity

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Impurity effects on superconductivity on surfaces of topological insulators. / Ito, Yuto; Yamaji, Youhei; Imada, Masatoshi.

In: Journal of the Physical Society of Japan, Vol. 81, No. 8, 084707, 01.08.2012.

Research output: Contribution to journalArticle

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