Fluctuating Forces Induced by Non Equilibrium and Coherent Light Flow

Eric Akkerman
Department of Physics, Technion Israel Institute of Technology, 32000 Haifa, Israel

In this work we present an unexpected example of fluctuation induced forces caused by classical light propagating in a scattering medium. In weakly disordered media, light intensity has long ranged spatial fluctuations (speckle) associated to mesoscopic coherent effects. These intensity fluctuations induce a new type of measurable radiation forces.

The effect is fully understood and characterized by means of an effective Langevin description of the light flow, where coherent mesoscopic effects are the source of the noise.

This approach is of particular interest since it maps the problem of coherent multiple light scattering onto an effective non equilibrium light flow. A clear asset of this type of approach is in its dependence upon two parameters only, thus making it a candidate to efficient machine learning algorithms.