Abstract

Over the last few years the third-order nonlinear optical properties of chalcogenide glasses has received much attention with regard to their ability to be used in ultrafast all-optical switching for optical communication. Optical fibres made from these glasses are used in the optical switching devices as they provide large interaction lengths. A large off-resonant nonlinearity with low linear and non-linear absorption loss is required for a smaller length of switching device. All-optical switching has been demonstrated in AS₂S₃ glass fibres but these suffer from the drawback of large two-photon absorption. Hence the thermal contribution to the optical nonlinearity due to two-photon absorption can become a dominant mechanism in high bit-rate system applications and should be avoided. The two-photon absorption is also known to cause the optical damage in the AS₂S₃ fibres at 1.3 µm.

© 2000 IEEE