Proximity-Induced Superconductivity in an Antiferromagnetic Mn Layer on Nb: First-Principles Study

Heterostructures made of superconductors and ferromagnetic or antiferromagnetic materials have recently drawn a lot of attention due to the possibility of realizing topological superconductivity and superconducting spintronics applications, which is allowed by the competitive or cooperative nature of the magnetic materials for the superconducting state. Recently, the proximity-induced superconducting state has been experimentally studied for Mn atomic layers on a Nb substrate by using scanning tunneling microscopy or spectroscopy. Motivated by this experiment, we investigate the proximity-induced superconducting state in the Mn layers for the Mn/Nb heterostructure, when the Mn layers have ferromagnetic order or antiferromagnetic order, by using the first-principles method. For this study, we solve the fully relativistic Bogoliubov-de Gennes equations for the heterostructure within the first-principles calculations based on multiple scattering theory, where all bands of the Nb and Mn are included with spin-orbit coupling. We compute momentum-resolved spectral functions of the superconducting state and other superconducting properties, and they are compared to the experimental data.