Mesoscopic p-wave superconductor near the phase transition temperature

TL;DR

This study investigates how finite-size and boundary effects influence the order parameter configurations of mesoscopic p-wave superconductors near their critical temperature, revealing a preference for time-reversal symmetric states and vortex structures depending on aspect ratio.

Contribution

It provides a detailed analysis of boundary and size effects on p-wave superconductors using Ginzburg-Landau and quasi-classical theories, highlighting the conditions for different ground states.

Findings

Ground state near critical temperature is time-reversal symmetric in most cases.

Large aspect ratio favors a real vector aligned with the rectangle's long side.

Critical aspect ratio induces vortex-like order parameter structures.

Abstract

We study the finite-size and boundary effects on a p-wave superconductor in a mesoscopic rectangular sample using Ginzburg-Landau (GL) and quasi-classical (QC) Green's function theory. Except for a square sample with parameters far away from the isotropic weak-coupling limit, the ground state near the critical temperature always prefers a time-reversal symmetric state, where the order parameter can be represented by a real vector. For large aspect ratio, this vector is parallel to the long side of the rectangle. Within a critical aspect ratio, it has instead a vortex-like structure, vanishing at the sample center.