Coherent backscattering of light by an inhomogeneous cloud of cold atoms

摘要: When a quasiresonant laser beam illuminates an optically thick cloud of laser-cooled rubidium atoms, the average diffuse intensity reflected off sample is enhanced in narrow angular range around direction exact backscattering. This phenomenon known as coherent backscattering (CBS). By detuning from resonance, we are able to modify light scattering mean-free path inside and record accordingly variations CBS cone shape. We then compare experimental data with theoretical calculations Monte Carlo simulations including effect polarization internal structure atoms. confirm that strongly affects enhancement factor show unusual shape atomic medium---approximately spherically-symmetric, Gaussian density profile---strongly width cone.