Possibility of reflectionless tunneling crossed transport at normal metal / superconductor double interfaces

TL;DR

This paper explores non-local transport phenomena at normal metal/superconductor double interfaces using theoretical models, revealing conditions for reflectionless tunneling and enhanced crossed conductance.

Contribution

It introduces a detailed analysis of non-local transport at NS double interfaces, highlighting the role of scatterers in enabling reflectionless tunneling.

Findings

Negative elastic cotunneling crossed conductance observed

Enhanced conductance with additional scatterers away from interfaces

Potential for reflectionless tunneling in specific contact configurations

Abstract

We investigate one dimensional models (the Blonder, Tinkham, Klapwijk model and a tight-binding model) of non local transport at normal metal / superconductor (NS) double interfaces. We find a negative elastic cotunneling crossed conductance, strongly enhanced by additional scatterers away from the interfaces, suggesting the possibility of reflectionless tunneling non local transport at double NS interfaces with contacts having a sufficiently small extension.