Generation of coherent light from a disordered medium

Summary form only given. Over the past two decades, there has been much progress in the study of light transport in a disordered dielectric medium. Most studies are within the framework of ray optics or wave optics. Quantum statistical properties of light in a random medium have received little attention. To bridge the gap between random media and quantum optics, we conducted an experimental study of photon statistics of random lasers. ZnO nanoparticles with an average diameter of 80 nm are cold-pressed to form a pellet. In the coherent backscattering experiment, the scattering mean free path is measured The frequency-tripled output of a picosecond Nd:YAG laser is used to optically excite the ZnO pellet. The ZnO emission is measured by a spectrometer which is connected to a streak camera.