Using geometry to manipulate long-range correlation of light inside disordered media

TL;DR

This paper experimentally shows that the shape of disordered photonic waveguides can be altered to control long-range light correlation, revealing shape-dependent non-universal behavior in wave transport.

Contribution

It introduces a method to manipulate long-range correlations in disordered media by changing waveguide geometry, highlighting non-local effects in mesoscopic wave transport.

Findings

Long-range intensity correlation can be shaped by waveguide geometry.

Correlation asymmetry depends on incident light direction.

Shape-dependent correlations break universality in diffusive transport.

Abstract

We demonstrate experimentally that long-range intensity correlation for light propagating inside random photonic waveguides can be modified by changing the shape of the waveguide. The functional form of spatial correlation is no longer universal in the regime of diffusive transport and becomes shape-dependent due to the non-local nature of wave propagation. The spatial dependence of the correlation may be asymmetric for light incident from opposite ends of the waveguide. This work opens the door to control non-local effects in mesoscopic transport of waves by manipulating the geometry of random systems.