OPTICAL SWITCHING DEVICE

摘要

PCT No. PCT/GB94/02240 Sec. 371 Date May 28, 1996 Sec. 102(e) Date May 28, 1996 PCT Filed Oct. 11, 1994 PCT Pub. No. WO95/10795 PCT Pub. Date Apr. 20, 1995A 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.