The role of plasma kinetics in the process of THz pulses generation and amplification

The article discusses the process of generation and amplification of short THz pulses taking into account kinetic properties of plasma formed in the process of tunnel ionization by the two-color laser femtosecond pulse, namely velocity distribution of plasma electrons. Analytical and numerical solutions of the dispersive equation for longitudinal oscillations show that the accounting of plasma kinetics can lead to essential variation of the spectral characteristics of a generated pulse thus leading to a change in signal duration. Subsequent additional amplification of the formed seed THz pulse during the propagation through the nonequilibrium Xe plasma channel formed by an intense femtosecond KrF laser pulse is analyzed.