Odd-parity pairing correlations in a d-wave superconductor

TL;DR

This paper theoretically investigates how spin-orbit interactions influence pairing symmetries in a 2D d-wave superconductor, revealing induced odd-frequency triplet correlations and their relation to surface states and proximity effects.

Contribution

It demonstrates that spin-orbit interactions induce odd-frequency triplet pairing correlations and explores their connection to surface states and the anomalous proximity effect.

Findings

Spin-orbit interactions induce spin-triplet p-wave correlations.

Odd-frequency s-wave pairing appears at the superconductor surface.

Results suggest potential for designing superconductors with strong proximity effects.

Abstract

We theoretically study the effects of spin-orbit interactions on symmetry of a Cooper pair in a spin-singlet d-wave superconductor in two-dimension. The pairing symmetry is analyzed in terms of the anomalous Green's function which is obtained by solving the Gor'kov equation analytically. A spin-orbit interaction induces a spin-triplet p-wave pairing correlation in a uniform superconductor. An odd-frequency spin-triplet s-wave pairing correlation appears at a surface of such superconductor as a result of breaking inversion symmetry locally. We also discuss a close relationship among the odd-frequency pairing correlation, chirality of surface bound states at the zero energy, and the anomalous proximity effect. The obtained results enable us to design a superconductor which causes the strong anomalous proximity effect.