Nonlinear delocalization on disordered Stark ladder

TL;DR

This paper investigates how weak nonlinearity affects wave localization in a disordered Stark ladder, revealing that nonlinearity induces subdiffusive delocalization while preserving the spreading exponent.

Contribution

It demonstrates that weak nonlinearity causes delocalization in a disordered Stark ladder, a novel insight into wave propagation under combined disorder and static field effects.

Findings

Nonlinearity induces subdiffusive spreading.

The spreading exponent remains similar to the linear case.

Delocalization occurs due to nonlinearity.

Abstract

We study effects of weak nonlineary on localization of waves in disordered Stark ladder corresponding to propagation in presence of disorder and a static field. Our numerical results show that nonlinearity leads to delocalization with subdiffusive spreading along the ladder. The exponent of spreading remains close to its value in absence of the static field.