Proximity effect in Nb-Mo layered films: Transition temperature and critical current dependence on period

TL;DR

This study investigates how the superconducting transition temperature and critical current density in Mo/Nb layered films are affected by the number of bilayer periods, revealing that these properties are largely independent of the number of layers.

Contribution

It provides experimental evidence that the transition temperature and critical current density in Mo/Nb multilayers do not decrease with increasing periods, challenging some theoretical expectations.

Findings

Transition temperature remains constant with increasing periods.

Critical current density scales independently of the number of bilayers.

Experimental results align with proximity effect theory in the dirty limit.

Abstract

The behavior of the transition temperature and critical current density for a Mo/Nb repeated bilayer system as a function of the number of periods was explored. The measured values of the transition temperature are compared to the theoretical predictions for the proximity effect in the dirty limit. We find that the transition temperature does not decrease as the number of periods increase. In addition, inductive critical current density measurements also show a scaling that indicates the superconductivity properties are not dependent on the number of bilayers.