  Nonlinear dynamics of establishment of electron-hole coherent superpositions
states in graphene by multiphoton resonant excitation of interband transitions
in laser fields is considered. The single-particle time dependent density
matrix for such a quantized system is calculated in the multiphoton resonant
approximation. The dependence of Rabi oscillations of Fermi-Dirac sea in
graphene on the time, momentum, and photon number at multiphoton
laser-excitation is analyzed.
