Nonclassical States of Light in Parametric Down-Conversion Process

Abstract

We study nonclassical states of light like squeezing and sub-poissonian in spontaneous and stimulated parametric down-conversion process. The amplitude-squared and amplitude-cubed squeezing effects of the radiation field in the fundamental mode are investigated and found to be dependent on the number of pump photons of the system. The photon statistics of the fundamental mode in this process have also been investigated and found to be sub-poissonian in nature. It is shown that the amplitude squeezing and sub-poissonian photon statistics of light occur simultaneously. It is observed that degree of squeezing and occurrence of sub-poissonian is directly associated with photon number in the fundamental mode of the optical field. The dependence of the amplitude squeezing in terms of signal to noise ratio on the number of photons is studied. It is found that maximum signal to noise ratio is possible in lower order i.e. in normal squeezing.