Abstract

Stable all-optical switching (AOS) was recently demonstrated¹ in a novel nonlinear fiber interferometer. In this, a coupler with an unequal splitting ratio (α: 1 − α) at the operating wavelength is used to form a fiber loop. When a high intensity pulse is launched into the coupler, a different amount of power is coupled info the two opposite propagation directions in the loop. This results in a differential phase delay along the two propagation directions, and the input pulse is reflected back or transmitted through the loop depending on the input intensity. Since the splitting ratio has to be close to 50:50 to achieve good switching modulation, the differential phase delay is low, and very high switching powers are required.

© 1990 Optical Society of America