170 research outputs found
Stokes parameters for light scattering from a Faraday-active sphere
We present an exact calculation for the scattering of light from a single
sphere made of Faraday-active material, to first order in the external magnetic
field. We use a recent expression for the T-matrix of a Mie scatterer in a
magnetic field to compute the Stokes parameters in single scattering that
describe completely flux and polarization of the scattered light.Comment: 17 pages, 5 figures, Latex, accepted for publication in JQSR
Transverse confinement of waves in 3D random media
We study the transmission of a tightly focused beam through a thick slab of
3D disordered medium in the Anderson localized regime. We show that the
transverse profile of the transmitted beam exhibits clear signatures of
Anderson localization and that its mean square width provides a direct measure
of the localization length. For a short incident pulse, the width is
independent of absorption.Comment: 4 pages, 3 figure
Role of mean free path in spatial phase correlation and nodal screening
We study the spatial correlation function of the phase and its derivative,
and related, fluctuations of topological charge, in two and three dimensional
random media described by Gaussian statistics. We investigate their dependence
on the scattering mean free path.Comment: 7 pages, 6 figures. submitted to Europhys. Let
Controlled manipulation of light by cooperative response of atoms in an optical lattice
We show that a cooperative atom response in an optical lattice to resonant
incident light can be employed for precise control and manipulation of light on
a subwavelength scale. Specific collective excitation modes of the system that
result from strong light-mediated dipole-dipole interactions can be addressed
by tailoring the spatial phase-profile of the incident light. We demonstrate
how the collective response can be used to produce optical excitations at
well-isolated sites on the lattice.Comment: 8 pages, 1 figur
Dynamics of weakly localized waves
We develop a transport theory to describe the dynamics of (weakly) localized
waves in a quasi-1D tube geometry both in reflection and in transmission. We
compare our results to recent experiments with microwaves, and to other
theories such as random matrix theory and supersymmetric theory.Comment: RevTeX, 4 pages, 2 figure
Dynamics of Anderson localization in open 3D media
We develop a self-consistent theoretical approach to the dynamics of Anderson
localization in open three-dimensional (3D) disordered media. The approach
allows us to study time-dependent transmission and reflection, and the
distribution of decay rates of quasi-modes of 3D disordered slabs near the
Anderson mobility edge.Comment: 4 pages, 4 figure
Mesoscopic phase statistics of diffuse ultrasound in dynamic matter
Temporal fluctuations in the phase of waves transmitted through a dynamic,
strongly scattering, mesoscopic sample are investigated using ultrasonic waves,
and compared with theoretical predictions based on circular Gaussian
statistics. The fundamental role of phase in Diffusing Acoustic Wave
Spectroscopy is revealed, and phase statistics are also shown to provide a
sensitive and accurate way to probe scatterer motions at both short and long
time scales.Comment: 4 pages, 4 figures, submitted to Physical Review Letter
Photonic Hall Effect in ferrofluids: Theory and Experiments
An experimental and theoretical study on the Photonic Hall Effect (PHE) in
liquid and gelled samples of ferrofluids is presented. The ferrofluids are
aqueous colloidal suspensions of Fe(_{2})CoO(_{4}) particles, which can be
considered as anisotropic and absorbing Rayleigh scatterers.
The PHE is found to be produced by the orientation of the magnetic moments of
the particles, as is also the case for the Faraday effect. The dependence of
the PHE with respect to the concentration of the scatterers, the magnetic field
and the polarization of the incident light is measured in liquid and in gelled
samples and is compared to a simple model based on the use of a scattering
matrix and the single scattering approximation.Comment: 20 pages, 11 figures, submitte
Coherent backscattering of light by atoms in the saturated regime
We present the first calculation of coherent backscattering with inelastic
scattering by saturated atoms. We consider the scattering of a
quasi-monochromatic laser pulse by two distant atoms in free space. By
restricting ourselves to scattering of two photons, we employ a perturbative
approach, valid up to second order in the incident laser intensity. The
backscattering enhancement factor is found to be smaller than two (after
excluding single scattering), indicating a loss of coherence between the doubly
scattered light emitted by both atoms. Since the undetected photon carries
information about the path of the detected photon, the coherence loss can be
explained by a which-path argument, in analogy with a double-slit experiment.Comment: 16 pages, 10 figure
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