Quantum Properties of an Andreev Phase Gradiometer

TL;DR

This paper introduces a novel nano-structure device based on superconducting phase gradients, demonstrating conductance oscillations influenced by phase changes and interface barriers, with potential applications in quantum sensing.

Contribution

It presents a new type of Andreev phase gradiometer leveraging phase gradient interference effects in superconductor-normal metal contacts.

Findings

Conductance oscillates with phase gradient v.

Presence of Schottky barrier enhances effect.

Oscillations observed in N-S-N structures.

Abstract

A new class of nano-structure devices is suggested, based on interference from the order parameter phase gradient of a single superconductor (S) in contact with a single normal metallic lead (N). By solving the Bogoliubov - de Gennes equation in two dimensions, it is demonstrated that the electrical conductance of a normal conductor of width $M$ in contact with a superconductor will oscillate as the phase gradient $v$ at 90$^0$ to the interface is increased. This effect is enhanced by the presence of a Schottky barrier at the interface and is also present in $N-S-N$ structures.