Abstract

Ultrafast photonic switching using third-order optical nonlinearities has been reported in dual-guide nonlinear directional couplers^1,2 (NDC's) and in a unique rocking-filter fibre switch³. In the second device, the two modes of a highly biréfringent fibre are coupled together by a periodic distortion that is induced during the pulling process by rocking the preform at the birefringent beat period. Nonlinear effects dephase the resonant condition, and switch the device. In this paper a somewhat analogous device is proposed and analysed. This is a periodically perturbed NDC that may be hundreds of coupling lengths L_c long.

© 1989 Optical Society of America