Cascade emission and four-wave mixing parametric processes in potassium

Abstract

Strong stimulated cascade emission and coherent four-wave parametric radiations are observed. By proper observation of the excitation spectra, the cascade emission and the coherent four-wave mixing parametric processes can be identified. The effect of the buffer gas pressure on the intensity and the pulse compression of the emitted radiation were investigated. Cascade inversionless coherent radiation emission with absorption reduction and third order nonlinear susceptibility enhancement due to the presence of a strong internally generated field are discussed for the 4p–4s strong emission observed.