Squeezing up to fourth-order in the pump mode of eight-wave mixing process

Squeezing of the electromagnetic field is investigated in the pump mode during an eight-wave mixing process under short time approximation on the basis of quantum mechanical approach. The coupled Heisenberg equations of motion involving real and imaginary parts of the quadrature operator are established. Occurrence of squeezing in the first, second, third and fourth-order field amplitude in the pump mode has been investigated. It depends upon the coupling constant ‘g’ and the phase values of the field amplitude. The process involves absorption of three pump photons of the same frequency, one pump photon of a different frequency and emission of four probe photons of the same frequency. The dependence of squeezing on photon number is established with investigations into the degree of squeezing in the first and higher order. The photon statistics of the pump mode in the process has also been investigated and found to be sub-Poissonian in nature.