Programmable branched flow of light

TL;DR

This paper demonstrates how anisotropic nematic liquid crystals can be used to program and control branched flow of light, revealing universal scaling laws and directional channeling effects for advanced photonic applications.

Contribution

It introduces a novel, programmable platform for controlling light flow using liquid crystals, connecting disordered photonics with mesoscopic wave transport.

Findings

Universal scaling law for branched light flow

Directional channeling under extreme anisotropy

Suppression of transverse spreading of light

Abstract

We demonstrate deterministic control of branched flow of light using anisotropic nematic liquid crystals. By sculpting the director field via photoalignment, we create spatially programmable optical potentials that govern light scattering and propagation. This platform enables configurable, anisotropic branched flow of light and reveals a universal scaling law for its characteristic features, directly connecting disordered photonics with mesoscopic wave transport. Under extreme anisotropy, we observe a pronounced directional channeling effect, driven by anomalous symmetry-breaking velocity diffusion, which concentrates light propagation along preferential directions while suppressing transverse spreading. These findings establish a tunable material platform for harnessing branched flow of light, opening pathways toward on-chip photonic circuits that exploit disorder-guided transport, scattering-resilient endoscopic imaging, and adaptive optical interfaces in complex media.