85
Double Fused 1.55 Micrometer Vertical Cavity Lasers for 80K Operation--Conductus, Inc., 969 West Maude Avenue, Sunnyvale, CA 94086-2802; 408-523-9458
Dr. Yongming Zhang, Principal Investigator
Mr. Ron Wilderink, Business Official
DOE Grant No. DE-FG03-99ER82768
Amount: $99,470
Ultra-wide bandwidth and low power dissipation make superconducting and cryogenic semiconductor electronics very attractive for routing and processing the vast amount of data acquired in high energy physics experiments. However, cryogenic circuits cannot be used to build an ultra-high-speed fiber optic link because typical commercial laser diodes have threshold currents that exceed 10 mA. A wide band, low threshold laser could enable cryogenic circuits to modulate lasers directly and make it possible to build a cryogenic fiber optic link for wideband data transmission. This project will develop a low-threshold, long-wavelength vertical cavity laser (VCL) operating around 80K. Recent advances make it possible to develop the VCL with submilliamp threshold current, 10 GHz modulation bandwidth, and optimized for low temperatures. Device fabrication will incorporate recent improvements in the design of GaAlAs/GaAs mirrors and the InGaAsP/InP multi-quantum well active region. In Phase I, the recently improved double-fused 1.55 µm vertical cavity lasers designed for room temperature operation will be investigated in detail at cryogenic temperatures. Devices for high-speed operation at 80K will also be designed, fabricated, and characterized.
Commercial Applications and Other Benefits as described by the awardee: This technology should impact future applications of superconducting electronics in fiber-optic communications, high energy physics instrumentations, cryogenic satellite communications, and the long-haul fiber-optical data transmission systems. Low cost, high performance vertical cavity lasers could also be used in fiber optic transport subsystems that could be implemented in future broadband wireless systems.