Coherent effects during propagation of ultrashort light pulses in a medium under two-photon interaction conditions

An analysis is made of the evolution of high-power laser pulses in the case of coherent two-photon interaction with resonant media. It is shown that pulses of frequencies $\omega_0$ and $\omega_s$ satisfying the equalit $\omega_0\pm\omega_s=\omega_{21}$ ($\omega_{21}$ is the resonance frequency of the medium) experience splitting into separate subpulses followed by a reduction in their duration and increase in their power. The efficiency of this process depends on the initial ratio of the amplitudes $\mathscr E_0$ and $\mathscr E_s$. It is shown that such effects can be observed in paramagnetic acoustic resonance.