Optical switching device

Abstract From the Canadian patent

A non-linear optical switch, includes a semiconductor optical gain medium. The switch is, arranged to switch a signal at a first wavelength in response, to a control signal at a second wavelength applied to the optical, gain medium. The refractive index of the gain medium is modified, in response to the control signal. An optical holding signal at a third wavelength is applied to the gain, medium. The optical holding signal pumps the optical gain medium and, thereby fixes the Fermi level. The switch may be embodied in OTDM, demultiplexers clock recovery, circuits, wavelength converters and other devices.