Localization in a random phase-conjugating medium

Observation of weak localization of light in a random medium.

Reflection of light from a disordered medium backed by a phase-conjugating mirror

This is a theoretical study of the interplay of optical phase-conjugation and multiple scattering. We calculate the intensity of light reflected by a phaseconjugating mirror when it is placed behind a disordered medium. We compare the results of a fully phase-coherent theory with those from the theory of radiative transfer. Both methods are equivalent if the dwell time τdwell of a photon in the...

Fermions in a Random Medium

We study the continuum field theory for an ensemble of directed polymers ri(t) in 1+d ′ dimensions that live in a medium with quenched point disorder and interact via short-ranged pair forces gΨ(ri − rj). In the strong-disorder (or low-temperature) regime, such forces are found to be relevant in any dimension d′ below the upper critical dimension for a single line. Attractive forces generate a ...

Depinning in a Random Medium

We develop a renormalized continuum field theory for a directed polymer interacting with a random medium and a single extended defect. The renormalization group is based on the operator algebra of the pinning potential; it has novel features due to the breakdown of hyperscaling in a random system. There is a second-order transition between a localized and a delocalized phase of the polymer; we ...

A ug 1 99 7 Reflection of light from a disordered medium backed by a phase - conjugating mirror

This is a theoretical study of the interplay of optical phase-conjugation and multiple scattering. We calculate the intensity of light reflected by a phaseconjugating mirror when it is placed behind a disordered medium. We compare the results of a fully phase-coherent theory with those from the theory of radiative transfer. Both methods are equivalent if the dwell time τdwell of a photon in the...