Abstract

An asymmetric Sagnac interferometer is capable of performing a variety of optical functions, such as ultrafast all-optical switching [1]. As a fibre-integrated device, the nonlinear optical loop minor (NOLM) is particularly suited for integration into fibre-optic systems for all-optical processing, signal regeneration and ASE discrimination in optical communication. Recently, deamplification of photon-number noise of coherent pulses below the shot-noise limit was predicted [2] and experimentally observed for the first time [3]. Here we present to our knowledge the strongest squeezing from a NOLM observed to date.

© 1998 IEEE