Superconductor-Ferromagnet Bi-Layers: a Comparison of s-Wave and d-Wave Order Parameters

TL;DR

This paper compares s-wave and d-wave superconductor-ferromagnet bi-layers, analyzing how ferromagnetic layer thickness affects critical temperature and density of states, revealing oscillatory behaviors and effects of d-wave rotation.

Contribution

It provides a comparative analysis of s-wave and d-wave superconductor-ferromagnet bi-layers, including the impact of d-wave rotation on critical temperature and density of states.

Findings

Critical temperature oscillates with ferromagnetic layer thickness for both s-wave and d-wave.

Rotated d-wave order parameter significantly alters critical temperature.

Density of states reflects oscillatory superconducting correlations.

Abstract

We study superconductor-ferromagnet bi-layers, not only for s-wave but also for d-wave superconductors. We observe oscillations of the critical temperature when varying the thickness of the ferromagnetic layer for both s-wave and d-wave superconductors. However, for a rotated d-wave order parameter the critical temperature differs considerably from that for the unrotated case. In addition we calculate the density of states for different thicknesses of the ferromagnetic layer; the results reflect the oscillatory behaviour of the superconducting correlations.