Time dependence of object wave amplitude at four-wave mixing with allowance for resonant and thermal nonlinearities

The analytical expression connecting the time dependence of spatial spectrum of object wave with the time dependence of spatial spectrum of signal wave has been obtained for degenerate four-wave radiation converter on resonant and thermal nonlinearities. It is shown, that simultaneous taking to account two types of nonlinearity lead to emergence of additional wave in an object wave. The connection of exit time to a steady-state value of this additional wave with exit time to a steady-state value of the object waves caused by existence only thermal or only resonant nonlinearities has been found.