Abstract

The bistable parametric resonance occurs in a crystal interacting with a biharmonic optical field if the difference between optical frequencies equals twice the vibrational frequency of a lattice mode [1,2].The square of the amplitude of the lattice vibrations, a, is resonantly enhanced and exhibits bistable behaviour with respect to both the difference frequency and the field amplitudes E and E'. The stationary dependence of a on E has the form of the unfoldings of pitchfork bifurcation [3], corresponding to different values of E' (Eig.1a). Although the pitchfork branches are separated we demonstrate the complex hysteresis loops linking those branches together (Fig.1b).

© 1985 Optical Society of America