Metamaterial control of stimulated Brillouin scattering

TL;DR

This paper demonstrates how metamaterials can be engineered to control stimulated Brillouin scattering (SBS) gain, achieving significant enhancement or suppression through numerical simulations and theoretical modeling.

Contribution

It introduces a general theoretical framework for SBS control in metamaterials and provides numerical examples showing substantial gain modulation using common materials.

Findings

Achieved over an order of magnitude gain enhancement with As$_2$S$_3$ spheres in silicon.

Demonstrated full suppression of SBS gain with GaAs spheres in silicon.

Showed complex dependence of gain on filling fraction and identified electrostriction as the key effect.

Abstract

Using full opto-acoustic numerical simulations, we demonstrate enhancement and suppression of the SBS gain in a metamaterial comprising a subwavelength cubic array of dielectric spheres suspended in a dielectric background material. We develop a general theoretical framework and present several numerical examples using technologically important materials. For As$_2$S$_3$ spheres in silicon, we achieve a gain enhancement of more than an order of magnitude compared to pure silicon, and for GaAs spheres in silicon, full suppression is obtained. The gain for As$_2$S$_3$ glass can also be strongly suppressed by embedding silica spheres. The constituent terms of the gain coefficient are shown to depend in a complex way on the filling fraction. We find that electrostriction is the dominant effect behind the control of SBS in bulk media.