Dirty two-band superconductivity with interband pairing order

Yasuhiro Asano (Corresponding Author), Akihiro Sasaki, Alexander A. Golubov

Research output: Contribution to journalArticleAcademicpeer-review

2 Citations (Scopus)
41 Downloads (Pure)

Abstract

We study theoretically the effects of random nonmagnetic impurities on the superconducting transition temperature Tc in a two-band superconductor characterized by an equal-time s-wave interband pairing order parameter. Because of the two-band degree of freedom, it is possible to define a spin-triplet s-wave pairing order parameter as well as a spin-singlet s-wave order parameter. The former belongs to odd-band-parity symmetry class, whereas the latter belongs to even-band-parity symmetry class. In a spin-singlet superconductor, Tc is insensitive to the impurity concentration when we estimate the self-energy due to the random impurity potential within the Born approximation. On the other hand in a spin-triplet superconductor, Tc decreases with the increase of the impurity concentration. We conclude that Cooper pairs belonging to odd-band-parity symmetry class are fragile under the random impurity potential even though they have s-wave pairing symmetry.

Original languageEnglish
Article number043020
Number of pages10
JournalNew journal of physics
Volume20
Issue number4
DOIs
Publication statusPublished - 12 Apr 2018

Fingerprint

superconductivity
impurities
parity
symmetry
Born approximation
degrees of freedom
transition temperature
estimates
energy

Keywords

  • interband pair
  • random impurities
  • superconductivity
  • transition temperature
  • random impurites

Cite this

@article{a5199466d7204437a3cf4dd5501a3b5f,
title = "Dirty two-band superconductivity with interband pairing order",
abstract = "We study theoretically the effects of random nonmagnetic impurities on the superconducting transition temperature Tc in a two-band superconductor characterized by an equal-time s-wave interband pairing order parameter. Because of the two-band degree of freedom, it is possible to define a spin-triplet s-wave pairing order parameter as well as a spin-singlet s-wave order parameter. The former belongs to odd-band-parity symmetry class, whereas the latter belongs to even-band-parity symmetry class. In a spin-singlet superconductor, Tc is insensitive to the impurity concentration when we estimate the self-energy due to the random impurity potential within the Born approximation. On the other hand in a spin-triplet superconductor, Tc decreases with the increase of the impurity concentration. We conclude that Cooper pairs belonging to odd-band-parity symmetry class are fragile under the random impurity potential even though they have s-wave pairing symmetry.",
keywords = "interband pair, random impurities, superconductivity, transition temperature, random impurites",
author = "Yasuhiro Asano and Akihiro Sasaki and Golubov, {Alexander A.}",
year = "2018",
month = "4",
day = "12",
doi = "10.1088/1367-2630/aab954",
language = "English",
volume = "20",
journal = "New journal of physics",
issn = "1367-2630",
publisher = "IOP Publishing Ltd.",
number = "4",

}

Dirty two-band superconductivity with interband pairing order. / Asano, Yasuhiro (Corresponding Author); Sasaki, Akihiro; Golubov, Alexander A.

In: New journal of physics, Vol. 20, No. 4, 043020, 12.04.2018.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Dirty two-band superconductivity with interband pairing order

AU - Asano, Yasuhiro

AU - Sasaki, Akihiro

AU - Golubov, Alexander A.

PY - 2018/4/12

Y1 - 2018/4/12

N2 - We study theoretically the effects of random nonmagnetic impurities on the superconducting transition temperature Tc in a two-band superconductor characterized by an equal-time s-wave interband pairing order parameter. Because of the two-band degree of freedom, it is possible to define a spin-triplet s-wave pairing order parameter as well as a spin-singlet s-wave order parameter. The former belongs to odd-band-parity symmetry class, whereas the latter belongs to even-band-parity symmetry class. In a spin-singlet superconductor, Tc is insensitive to the impurity concentration when we estimate the self-energy due to the random impurity potential within the Born approximation. On the other hand in a spin-triplet superconductor, Tc decreases with the increase of the impurity concentration. We conclude that Cooper pairs belonging to odd-band-parity symmetry class are fragile under the random impurity potential even though they have s-wave pairing symmetry.

AB - We study theoretically the effects of random nonmagnetic impurities on the superconducting transition temperature Tc in a two-band superconductor characterized by an equal-time s-wave interband pairing order parameter. Because of the two-band degree of freedom, it is possible to define a spin-triplet s-wave pairing order parameter as well as a spin-singlet s-wave order parameter. The former belongs to odd-band-parity symmetry class, whereas the latter belongs to even-band-parity symmetry class. In a spin-singlet superconductor, Tc is insensitive to the impurity concentration when we estimate the self-energy due to the random impurity potential within the Born approximation. On the other hand in a spin-triplet superconductor, Tc decreases with the increase of the impurity concentration. We conclude that Cooper pairs belonging to odd-band-parity symmetry class are fragile under the random impurity potential even though they have s-wave pairing symmetry.

KW - interband pair

KW - random impurities

KW - superconductivity

KW - transition temperature

KW - random impurites

UR - http://www.scopus.com/inward/record.url?scp=85046662132&partnerID=8YFLogxK

U2 - 10.1088/1367-2630/aab954

DO - 10.1088/1367-2630/aab954

M3 - Article

VL - 20

JO - New journal of physics

JF - New journal of physics

SN - 1367-2630

IS - 4

M1 - 043020

ER -