Enhanced mesoscopic correlations in dynamic speckle patterns

TL;DR

This paper investigates how mesoscopic correlations in speckle patterns evolve over time in disordered waveguides, revealing a linear growth in long-range correlations that surpasses continuous wave values, with implications for understanding interference phenomena.

Contribution

It demonstrates the linear increase of long-range speckle correlations over time in disordered media, extending understanding of mesoscopic interference effects beyond steady-state conditions.

Findings

Long-range correlations grow linearly with time.

Correlations can exceed steady-state values.

Results align with recent microwave experiments.

Abstract

We study the temporal evolution of speckle patterns in transmission of short wave pulses through a disordered waveguide. In the diffuse regime, the short-range spatial structure of speckles is the same as for continuous wave (cw) illumination, whereas the long-range correlation between distant speckle spots grows linearly with time and can exceed its cw value. We discuss the physical origin of this phenomenon, compare our results to recent microwave experiments, and suggest that a similar linear growth with time should also be characteristic for other mesoscopic interference phenomena.