Study on quantum theory of ultrashort pulse lasers

In this paper, a new ultrashort pulse lasers model has been established, which includes the nonlinear effects. A quantum mode-locked equation has been derived using the Hamiltonian function for the system of lasers on the basis of the model. The solutions for pulse field and photon distribution are obtained. We have examined the dependence of the pulse energy, width, and chirp on the laser parameters in steady state, after replacing the envelope operator by the envelope of the pulse in the equation. For the first time, we have discovered the self- steady characteristic of the ultrashort pulse lasers, and some methods that can be used to reduce the pulse width and improve the stability of the lasers are given.