Polariton-Biexciton Nonlinear Nutation and Stationary Spectrum Renormalization

Two macrofilled coherent modes ‐ a polariton and a biexciton one ‐ are assumed to exist simultaneously in a direct‐gap semiconductor. These modes are characterized by the sets of parameters kO ωo and qo = 2ko, Ω0 = 2ω0, where k0 is the wave vector of the polariton mode and ω0 is the external pumping frequency. In the stationary case the renormalized dispersion and the particle concentrations of the strong modes k0 and q0 are obtained. A selfconsisted equation for the quasi‐momentum k0 as a function of the frequency ω0 and the external pumping intensity is deduced. in the nonstationary limit the polariton and biexciton concentrations are found to vary periodically in time within certain ranges passing through their steady equilibrium values which are the same as the stationary ones. [Russian Text Ignored]