Laser Plasma Interaction and Non-classical Properties of Radiation Field

We show by explicit calculations that non-classical states of the radiation field can be produced by allowing short term interaction between a coherent state of the radiation field with plasma. Whereas, long term interaction, which thermalizes the radiation field, can produce non-classical states of the radiation field only at sufficiently small temperatures. A measure of k-th order squeezing, stricter than the one proposed by Zhang et al, is used to check the emergence of squeezing. It is also shown that photons in the considered thermalized field would follow super-Poissonian statistics.