Four-wave mixing on thermal nonlinearity with feedback for signal or object waves

The coincidence of the amplitude reflection coefficients, half-widths spatial frequencies bands a four-wave radiation converter on thermal nonlinearity with feedback for signal or object waves has been shown at equal pump intensity. dependence coefficient, selectivity intensity analyzed. An increase in half-width frequency band is observed an compensation phase shift arising as result propagation medium. There threshold value intensity, above which coefficient waves, less than absence feedback.