Sharpening of enhanced backscattering peak in a disordered gain medium

Sharpening of enhanced backscattering peak in a disordered gain medium.

We study theoretically the phenomenon of enhanced backscattering ~EBS! from a bulk disordered gain medium due to the presence of a dye and a pump beam. We show that the presence of the gain, in combination with the effect of saturation, can dramatically sharpen the EBS peak function. In the particular case of a point source incidence for the probe beam along with the presence of a plane-wave pu...

Dynamics of random laser and coherent backscattering of light from ZnO amplifying random medium

We investigated the dynamics of coherent backscattering cone and random laser in a disordered gain medium of ZnO powder. Theoretical fit to the coherent backscattering cone yields a transport mean free path l approximately equal to the probe wavelength , indicating that the scattering process is in the strong scattering regime. Supernarrow emissions from the laser are accompanied by enhancement...

Coherent backscattering of a picosecond pulse from a disordered medium: Analysis of the pulse shape in the time domain.

Enhanced backscattering in a converging-beam configuration.

Enhanced backscattering (EBS) is investigated for a converging-beam geometry. We find that the functional form of the enhanced backscattering cone is preserved under a change of variables that involves the focal length of the lens and the lens-to-sample distance. In absolute terms, the effect of the lens is that the EBS enhancement cone is lowered in magnitude and narrowed in angle. The experim...

Faraday rotation in a disordered medium

The Faraday rotation angle is calculated in a diffusive regime on a three-dimensional disordered slab. It is shown that tan is (i) an oscillating function of the magnetic field or the medium’s internal properties, and (ii) proportional to the ratio of the inelastic mean-free path lin to the mean-free path l, that is, to the average number of photon scatterings. The maximum rotation is achieved ...