The research of parametric interaction on testing by a probe field

Summary form only given. The carried out research of parametric interaction at pumping by narrow-band radiation close to transition 3²P₁2/ → 3²S₁2/ of sodium atom have shown the presence of three spectral lines in a spectrum of a scattered radiation registered on coming out of a heat pipe. Two lines symmetrically displaced from a transition frequency 3²P₁2/ → 3²S₁2/ are associated with a frequency-nondegenerate four-photon scattering, and the line shifted in the red side- with four-photon mixing on a system quasilevel of sodium atom. The method of probe field was used for the purpose of verification. In experiments with a probe field as testing radiation the wideband emission of a dye luminescence, i.e. continuous spectrum was used. This probe field was collinear with narrow-band emission of dye laser. The concentration of sodium atoms, measured on a method of a total absorption, during experiments was about 10¹⁴ cm^-3. As buffer gas in a heat pipe with sodium the neon was used on pressure 600 torr. The intensity of the narrow-band laser emission was about 500 kW/cm². The large angular divergence of the radiation coming out of pipe is the characteristic of the one. The radiation was diffused in a cone.