Laser converter with modified pumping and frequency-squeezed noise

A new principle of a parametric optical amplifier of the reflection type with a controlled backward wave is proposed. The excess noise in such a laser converter, due to zero-point fluctuations of a photodetector acting as a black body absorber, is suppressed by using an additional circulator window which provides coupling to a series of degenerate reflection-type parametric amplifiers tuned to combination frequencies. A squeezed state of the electromagnetic field inside the converter resonator observed at the combination frequencies can be used to detect ultrasmall signals. An expression is obtained for the calculation of the threshold sensitivity.