High-resolution spectroscopy at steady-state lasing with multiphoton backscattering

Abstract

A steady-state self-consistent lasing regime in a laser cavity is investigated with allowance for the back action of the output radiation at four-wave low-frequency scattering in the external sample. The scattering is by the photoelastic potential in the field of the additional opposing laser. General expressions for steady-state amplitudes of field oscillation in the cavity are obtained and employed for investigation of lasing features. Experiments were carried out with narrow-band (line width 1 MHz) continuously tunable diode lasers. The four-wave scattering occurred in solid and liquid dielectrics. It is shown that the fourwave scattering of the pumping laser radiation into the cavity of the signal laser substantially changes its lasing spectrum and can be used to measure dispersion of acousto-optic parameters.