Phase separation and proximity effects in itinerant ferromagnet-superconductor heterostructures

TL;DR

This paper investigates how proximity effects influence ferromagnet-superconductor heterostructures using a correlated single-band model that self-consistently accounts for induced ferromagnetism and phase separation near interfaces.

Contribution

It introduces a self-consistent approach to study proximity effects in heterostructures, revealing features like phase separation absent in traditional Zeeman field models.

Findings

Induced ferromagnetism affects interface properties.

Phase separation occurs near the interface.

Competition between magnetism and superconductivity is observed.

Abstract

Heterostructures made of itinerant ferromagnets and superconductors are studied. In contrast to most previous models, ferromagnetism is not enforced as an external Zeeman field but induced in a correlated single-band model (CSBM) that displays itinerant ferromagnetism as a mean-field ground state. This allows us to investigate the influence of an adjacent superconducting layer on the properties of the ferromagnet in a self-consistent Bogoliubov-de Gennes approach. The CSBM displays a variety features not present in the Zeeman exchange model that influence the behavior of order parameters close to the interface, as e.g. phase separation and the competition between magnetism and superconducting orders.