Amplification of squeezed light in the regime of triggered optical superradiance

The possibility of amplification of pulses of squeezed light in the regime of triggered optical superradiance is analysed. The kinetic equations are obtained which describe the dynamics of cooperative development of the population inversion and dispersion of the quadrature components of polarisation of optical centres interacting with the triggering-pulse field in the squeezed vacuum state. The dependence of the squeezing degree of the superradiance field on the squeezing degrees of the triggering-pulse field and polarisation of an amplifying medium is determined. It is shown that in the case of a sufficiently strong squeezing of the medium, the intensity of the squeezed quadrature component of the superradiance signal is lower than that of an incoherent spontaneous background. Therefore, the superradiance field can be characterised not only by a classical squeezing (when the dispersions of quadratures are not identical) but also by a quantum squeezing (when the dispersion of one quadrature is smaller than its vacuum value).