SBIR-STTR Award

Compact arrays of ultra-high-speed analog laser sources or lasers integrated with modulators are needed for LADAR sensors and scene generation. Multiplex, UCLA and UCSD propose a novel Monolithic Injection-Locked Analog Transmitter Array (MILATA) for wide frequency range (>2GHz) operation with greater than 60 dB optical extinction ratio. MILATA is a versatile technology platform that is built on our recent success in monolithic injection-locked lasers funded by DARPA RFLICS program. The monolithic injection locked laser we invented is the most compact and practical injection-locked semiconductor laser. It can be packaged in industry standard module with an output fiber pigtail. For LADAR scene generation, the injection locked laser will be monolithically integrated with electroabsorption modulators (EAM). A selective area growth method for InGaAsP based materials will be optimized for chip-scale transmitter array manufacturing. The output of Phase I of this program will be prototype MILATA chips packaged with discrete injection-locked lasers and EA modulators that are fully characterized to demonstrate the device design and performance. A novel quarter-wave shifted DFB laser with strong gratings will be fabricated for high device yield, which is necessary for array integration. Scalability for high-density array on the chip and packaging with electronics will also be investigated in Phase I for selecting the best approaches for an 8-channel transmitter array in Phase II, with the potential for 2-D integration up to a 256 by 256 element array. The proposed MILATA is a general-purpose, application-specific photonic IC technology that can be tailored to both DOD (LADAR scene generation, RF photonic links, phased array radars, millimeter wave generation) and commercial applications (CATV, high speed digital networks, WDM transmitter arrays for long-haul and metro/access systems). The technology fits Multiplex’s continuing marketing roadmap, and the ability for different applications to share the same technology platform is the key to cost reduction.

Benefits:
The proposed MILATA is a versatile technology platform for multiple-channel wide-bandwidth analog signal generation. The chip-scale integration of high-density lightwave transmitter arrays and packaging technology developed in this program addresses the key issues of cost, size and power consumption for Ladar scene simulators, and is anticipated to have potential impact on CATV and other fiber-linked or free-space analog RF systems. The technology developed in this project can also find applications in digital communication systems, where multiple-channel wavelength division multiplexed transmitter arrays are low-cost approaches especially for Metro and Access networks.

Keywords:
Analog Photonics, RF Photonics, Electro-absorption Modulator, Injection Locking, Injection-locked Laser, Ladar Projector, Radar Simulator, Arbitrary Waveform Generation, Phased Array

Compact arrays of ultra-high-speed analog laser sources or lasers integrated with modulators are needed for LADAR sensors and scene generation. Multiplex, Inc., UC Berkeley and UCSD propose a novel Monolithic Injection-Locked Analog Transmitter Array (MILATA) for wide frequency range (>2GHz) operation with 60 dB to 72 dB optical extinction ratio. MILATA is a versatile technology platform that is built on our recent success in monolithic injection-locked lasers funded by DARPA RFLICS program. The monolithic injection locked laser we invented is the most compact and practical injection-locked semiconductor laser. For LADAR scene generation, the injection locked laser will be monolithically integrated with an electro-absorption modulator (EAM). Direct modulation of the injection locked laser will be combined with external modulation using the monolithically integrated EAM for the proposed LADAR simulators. A novel quarter-wave shifted DFB laser with strong gratings will be fabricated for high device yield, which is necessary for array integration. A long-interaction-length EA modulator design with low waveguide propagation loss will be used for high optical extinction ratio while maintaining high modulation speed. A selective-area MOCVD (metal organic chemical vapor deposition) method for InP-GaInAsP based materials will be optimized for high-density, chip-scale transmitter array integration. The output of this SBIR Phase-II program will be a fully packaged MILATA with 8 fiber channels per card. The 8-channel transmitter arrays can be stacked on the fiber output side to form a 2-dimensioanl 8 x 8 array. We will pursue the development of manufacturing technologies for growing from 8 x 8 to 256 x 256 fiber channels. The proposed MILATA is a general-purpose, application-specific photonic IC technology that can be tailored to both DOD (LADAR scene generation, RF photonic links, phased array radars, millimeter wave generation) and commercial applications (parallel optical interconnect in next generation super computers, CATV distribution, high speed digital data links, and instrumentation). The technology fits Multiplexís continuing marketing roadmap, and the ability for different applications to share the same technology platform is the key to cost reduction.

Keywords:
Analog Photonics, Rf Photonics, Electro-Absorption