SYMMETRY-BREAKING IN OPTICAL-DYNAMICS OF 2 BISTABLE THIN-FILMS

A theoretical investigation is reported of the interaction of light wi th a system of two films which contain two-level centres and whose thi ckness is less than the incident radiation wavelength. It is shown tha t when light of the same intensity is incident from both sides of the films, symmetry-breaking bifurcation is possible, i.e. the transmitted fields are different for the opposite directions. The relationship be tween symmetry-breaking bifurcation and optical bistability is determi ned. If the distance between the films represents an odd number of the optical half-wavelengths, symmetry breaking occurs at a lower value o f the parameter representing the interaction nonlinearity than that co rresponding to the onset of bistability. The opposite is true when an even number of half-wavelengths can be fitted between the films. The s uppression of symmetry-breaking bifurcation is illustrated for various intensities of the incident optical field.