Ultrafast dephasing of light in strongly scattering GaP nanowires

TL;DR

This paper reports ultrafast light dephasing in strongly scattering GaP nanowires, enabling nonlinear control of photonic modes with potential applications in nanophotonics and random lasers.

Contribution

It demonstrates ultrafast dephasing in GaP nanowires and separates nonlinear effects, providing a quantitative model for ultrafast control of light in disordered media.

Findings

Dephasing time of 1.2 ps measured.

Nonlinear intensity modulation 100 times larger than bulk GaP.

Quantitative agreement with numerical models.

Abstract

We demonstrate ultrafast dephasing in the random transport of light through a layer consisting of strongly scattering GaP nanowires. Dephasing results in a nonlinear intensity modulation of individual pseudomodes which is 100 times larger than that of bulk GaP. Different contributions to the nonlinear response are separated using total transmission, white-light frequency correlation, and statistical pseudomode analysis. A dephasing time of $1.2\pm 0.2$~ps is found. Quantitative agreement is obtained with numerical model calculations which include photoinduced absorption and deformation of individual scatterers. Nonlinear dephasing of photonic eigenmodes opens up avenues for ultrafast control of random lasers, nanophotonic switches, and photon localization.