Conductance spectroscopy in ferromanget/superconductor hybrids

TL;DR

This paper presents a theoretical analysis of conductance in ferromagnet/superconductor hybrid structures with non-collinear magnetizations, revealing how interface transparency influences the manifestation of triplet superconducting correlations.

Contribution

The study introduces a model for the proximity effect in F-SFF-F structures with arbitrary exchange fields and non-collinear magnetizations, analyzing conductance features related to triplet correlations.

Findings

Zero-bias peak for perfect interface transparency

Two-peak structure for finite interface transparency

Interface features as diagnostic tools for hybrid structures

Abstract

We present theoretical model for the proximity effect in F-SFF-F structures (F is ferromagnet, S is superconductor) with non-collinear magnetizations vectors in the F-layers and with arbitrary magnitudes of exchange fields. Electrical conductance of these structures is analyzed within the Keldysh-Usadel formalism in the diffusive regime as a function of a misorientation angle between magnetizations of the F-layers and transparencies of SF and FF interfaces. We show that long-range triplet superconducting correlations manifest themselves either as a zero-bias peak in the case of perfect transparency of FF interface, or as a two-peak structure in the case of finite transparency. The predicted features may serve as a diagnostic tool for characterization of interfaces in superconducting hybrid structures