Dirty two-band superconductivity with interband pairing order

Abstract

We study theoretically the effects of random nonmagnetic impurities on the superconducting transition temperature $T_c$ in a two-band superconductor characterized by an equal-time s-wave interband pairing order parameter. The Fermi-Dirac statistics of electrons allows a spin-triplet s-wave pairing order as well as a spin-singlet s-wave order parameter due to the two-band degree of freedom. In a spin-singlet superconductor, $T_c$ 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, $T_c$ 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.

7 pages, 2 figures embedded

References in corpus (5)

• Iron-Based Superconductors: current status of materials and pairing mechanism
• Effects of surface roughness on the paramagnetic response of small unconventional superconductors
• Unexpected impact of magnetic disorder on multiband superconductivity
• Pair breaking due to orbital magnetism in iron-based superconductors
• Green function theory of dirty two-band superconductivity

Cited by in corpus (7)

• Robust parity-mixed superconductivity in disordered monolayer transition metal dichalcogenides
• The Role of Odd-Frequency Pairing in Multiband Superconductors
• Josephson effect in two-band superconductors
• Controllable odd-frequency Cooper pairs in multi-superconductor Josephson junctions
• Green function theory of dirty two-band superconductivity
• Superconductivity in Cu-doped Bi${}_2$Se${}_3$ with potential disorder
• Odd-frequency pairs and anomalous proximity effect in nematic and chiral states of superconducting topological insulators