# Reversal of Nonlocal Vortex Motion in the Regime of Strong Nonequilibrium

## TL;DR

This paper explores nonlocal vortex motion in a-NbGe nanostructures, revealing sign reversals of nonlocal voltage driven by high currents, explained by nonequilibrium magnetization and electron heating effects.

## Contribution

It uncovers a novel reversal of nonlocal vortex motion driven by strong nonequilibrium effects in superconducting nanostructures.

## Key findings

- Sign reversals of nonlocal voltage at high currents
- Dependence of sign reversal on temperature and current polarity
- Quantitative explanation via nonequilibrium magnetization and electron heating

## Abstract

We investigate nonlocal vortex motion in weakly pinning a-NbGe nanostructures, which is driven by a transport current I and remotely detected as a nonlocal voltage Vnl. At high I, the measured Vnl exhibits dramatic sign reversals that at low and high temperatures T occur for opposite polarities of I. The sign of Vnl becomes independent of that of the drive current at large abs(I). These unusual effects can be nearly quantitatively explained by a novel enhancement of magnetization, arising from a nonequilibrium distribution of quasiparticles at high T, and a Nernst-like effect resulting from local electron heating at low T.