Detection of a diffusive cloak via second-order statistics

TL;DR

This paper introduces a method to detect diffusive cloaks by analyzing second-order intensity correlations, revealing the cloak's size, position, and depth, and highlighting the potential to control wave statistics in turbid media.

Contribution

The study presents a novel detection scheme based on second-order statistics to identify diffusive cloaks, advancing understanding of wave interference in diffusive media.

Findings

Second-order intensity correlations are sensitive to cloaks' location and size.

The method can determine the depth of the diffusive cloak.

Wave statistics can be manipulated separately in turbid media.

Abstract

We propose a scheme to detect the diffusive cloak proposed by Schittny et al [Science 345, 427 (2014)]. We exploit the fact that diffusion of light is an approximation that disregards wave interference. The long-range contribution to intensity correlation is sensitive to locations of paths crossings and the interference inside the medium, allowing one to detect the size and position, including the depth, of the diffusive cloak. Our results also suggest that it is possible to separately manipulate the first- and the second-order statistics of wave propagation in turbid media.