High power, high efficiency diode lasers operating in the 15xx nm wavelength range are required for many applications, both in the military and in the commercial domains. Applications include eye-safe infrared illuminators, free-space optical (FSO) communication transmitters, LIDAR and range finder sources, as well as resonant pumping of Erbium-doped fiber or solid-state lasers for high energy lasers. In this paper, we will discuss our recent progress in developing high power, high efficiency stripe geometry and Master Oscillator Power Amplifier (MOPA) lasers operating at 1550 nm. MOPA lasers are fabricated in a monolithic platform in which we have engineered the epitaxial structure to mitigate Auger and other loss mechanisms. This device structure includes a single mode seed laser that feeds a tapered power amplifier. We have demonstrated single spatial mode performance of over 1 W output power (CW) and Electro-Optic (EO) power conversion efficiency of 44%. This EO efficiency is significantly higher than what is available today for 15xx nm lasers. The single spatial mode nature of these lasers has been verified through M^2 measurements. The MOPA shows a small-signal bandwidth >2GHz under direct modulation, offering a unique capability for free-space optical link applications. Stripe geometry lasers have been demonstrated generating in excess of 3 W output power (CW) with high EO efficiency (36%). While custom packaging is available, the MOPA lasers have been packaged into TO cans with collimating optics to enable easy integration into existing system architectures.
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