United States of America As Represented by the Secretary of the Air Force

Cornell Research Foundation Inc.

Michael A Parker

Paul David Swanson

Douglas Bourne Shire

Chung L Tang

Stuart I Libby

James S Kimmet

Chung C Tang

Richard J Michalak

The present invention demodulates a FM, WM or AM optical input beam, amplifies the signal impressed on the beam, and then modulates without intervening electronics the signal amplitude of an output beam. The apparatus can be made from any semiconductor laser, including edge-emitting lasers and VCSELs. Light transmitted through the waveguide (the &ldquo;control beam&rdquo;) interacts with the carrier population of the laser, reducing the available gain and thereby the output intensity. The present invention has three key advantages: (i) a FM control beam produces an amplitude-modulated output beam from the main-laser, (ii) the amplitude of the AM beam depends directly on the differential gain &part;G/&part;&ohgr;, and (iii) the apparatus and method provides gain for all LOGiC devices. The present invention works with available and future semiconductor lasers, including those emitting in the blue as well as those operating at 670, 850, 980, 1300, and 1500 nm. The 1300 and 1500 nm lasers are of particular importance for fiber communications.

Demodulating and amplifying systems of lasers with optical gain control (DAS-LOGiC)

The Vertical-cavity-surface-emitting Lasers with Optical Gain Control (V-LOGIC) form a family of integrated optical smart pixels for interconnect and signal processing applications. V-LOGIC devices consist of Vertical Cavity Surface Emitting Lasers (VCSELs) and In-Plane Lasers. (IPL) with cross-coupled cavities. The devices can operate in a digital, an analog or a hybrid mode. The IPLs either fully quench or modulate the VCSEL depending on whether the device is used in the digital or analog mode. In the Hybrid mode, one IPL serves as an enable input while another one modulates the VCSEL. The V-LOGIC devices can operate significantly faster than modulated lasers since, for the quenching phenomena, (1) the VCSEL carrier population is essentially constant and (2) the quenching is all-optical and does not require intermediate drive electronics. The family of devices solve the leading outstanding problems in optical switching and interconnect technologies. In particular, they form the basis for multiplanar optical signal processors, N.times.M optical routers, ATM and packet switching fabrics, and multi-chip modules.

Vertical cavity surface emitting lasers with optical gain control

Configurable Optical Gates (COGs) are used to transmit and receive optical signals similar to an interconnect device as well as perform a logic function on those signals (they are smart pixels). COGs consist of a laser with an intracavity modulator, an integrated current source and one or more integrated photodetectors to drive the modulators. The devices are monolithically integrated on MultiQuantum Well (MQW) heterostructure. Certain logic functions require that the bottom N- contact which is under individual devices be accessible and electrically isolated from neighboring devices. For this reason, the laser heterostructure is grown on a semi-insulating substrate. Each COG has a built-in light baffle that prevents the laser emission from coupling into the photodetectors. The optical detection of the COG can be disabled during fabrication and the device can be directly modulated by conventional electronics.

Apparatus using diode laser logic to form a configurable optical gate

Optical laser amplifier devices are formed integrally with spontaneous emission filters. The filtering function is accomplished by a laser amplifier whose output is employed to quench the signal generated by a laser. The quenching of the laser is performed in direct proportion to the stimulated emission component of the laser amplifier output signal. Since the stimulated emission component represents the output signal minus any spontaneous emission noise, the output signal generated by the laser is an amplified, inverted version of the input signal without the noise components. In the preferred embodiments, optical waveguides are employed to form the laser amplifier and the laser is either a horizontal cavity edge emitting laser or a vertical cavity surface emitting laser (VCSEL).

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Liverpool, NY, United States of America

Michael A Parker