# Transverse Shift in Andreev Reflection

## TL;DR

This paper predicts a universal transverse shift in Andreev reflection caused by spin-orbit coupling, especially prominent in Weyl semimetals, leading to a chirality-dependent Hall effect for reflected holes.

## Contribution

It introduces the concept of a universal transverse shift in Andreev reflection due to spin-orbit coupling, applicable to general 3D metals, and highlights its significance in Weyl semimetals.

## Key findings

- Pronounced transverse shifts in Weyl semimetals.
- Opposite shifts for different chirality electrons.
- Existence of the shift in general spin-orbit-coupled metals.

## Abstract

An incoming electron is reflected back as a hole at a normal-metal-superconductor interface, a process known as Andreev reflection. We predict that there exists a universal transverse shift in this process due to the effect of spin-orbit coupling in the normal metal. Particularly, using both the scattering approach and the argument of angular momentum conservation, we demonstrate that the shifts are pronounced for lightly-doped Weyl semimetals, and are opposite for incoming electrons with different chirality, generating a chirality-dependent Hall effect for the reflected holes. The predicted shift is not limited to Weyl systems, but exists for a general three-dimensional spin-orbit- coupled metal interfaced with a superconductor.