QUASIDISTRIBUTIONS FOR FREQUENCY-CONVERTER MODEL

We generalize, for arbitrary initial fields, the Glauber-Mista theorem of classical-like evolution of the frequency converter. We show, by s olving completely the Orlov-Vedenyapin diagonalization problem, that t he initially nonclassical fields remain nonclassical during the evolut ion: of the frequency converter. We give a general expression for the two-mode Husimi Q-function and examples of its marginal (single-mode) quasidistributions for, initial coherent states; Fock states and two-s tate superposition of Fock states. We find their graphical representat ions.