Coherent backscattering in a disordered optical medium in the presence of saturation absorption

We theoretically describe the coherent backscattering peak in a disordered medium in the presence of saturation absorption. When the excitation intensity is increased above the saturation intensity, the reflectivity of the incident light increases and the width of the peak becomes narrow. This effect is evident when the absorption length is comparable to the transport mean free path. The effect of the saturation absorption on the peak is compared with the effects of the normal absorption and the confined geometry.