Active reflection via a phase-insensitive quadratic nonlinear interaction within a microcavity

The reflectivity of a microcavity filled with a quadratic nonlinear materia l is shown to be actively changed by the interaction of two waves. Within t his microcavity, the reflection coefficient of a weak wave at the fundament al frequency is changed from almost 0% to a value in the vicinity of 100% b y the simultaneous incidence of an intense wave at the second-harmonic freq uency. This change in reflectivity is shown to be in a large degree insensi tive to the input phase difference between the two waves. (C) 1999 American Institute of Physics. [S0003-6951(99)01102-X].