Spatial–temporal frequency band of optical parametric amplifier

The spatial–temporal frequency band of optical parametric amplifier for collinear as well as for noncollinear phase-matching is analyzed taking into account angular dispersion of amplified pulsed beam. The simple formulae are derived which make possible determination of the largest frequency bands of parametric amplifiers in noncollinear geometry. It has been demonstrated that a shape of the spatial–temporal frequency band of optical parametric amplifier essentially depends on pump and signal wavelengths, and certain angular dispersion as well as proper beamwidth of signal pulse enable amplification of ultrashort pulses with duration of a few femtoseconds.