Optoelectronic switching node

Abstract

An optoelectronic switching node is disclosed wherein two input optical beams can be switched in the sense that they can be regenerated in either one of two output spatial locations in response to input control signals. Each one of the input optical beams is coupled to a resonant cavity detector which generates a current when its corresponding optical beam impinges on its resonant cavity. Output optical beams are regenerated by two inversion channel lasers each one of which has emitter, source and sub-collector terminals and is bistable in the sense that it can be switched on and off by currents delivered into and taken out of its source terminal. Heterojunction field effect transistors are used to selectively couple the currents generated by the resonant cavity detectors to the source terminals of the lasers in order to turn them on. Two heterojunction field effect transistors are each connected as a two terminal impedance between the source terminal of each laser and a reference potential in order to turn the laser off when no current is being provided by a detector. Two additional heterojunction field effect transistors are also connected as two terminal load impedances for each of the lasers. All of the devices are fabricated on a single wafer using a single epitaxial growth.

Dependencies are inferred from the claim text.