FIBERTEK, INC. — Department of Defense SBIR Phase I: N221-041

Description

The Agile Waveform, Spectrally Optimized, Midwave (AWSOM) laser system has been designed to meet the Navy’s needs for a compact and reliable high-power laser source in the midwave infrared (MWIR) spectral region.  The pump laser is a high-power thulium-doped fiber (Tm:fiber) amplifier.  Operation around two microns is required for parametric down-conversion to the MWIR bands of interest at high efficiency.  The objective is to develop and demonstrate a Tm:fiber amplifier with a 200 W average power and sufficient peak power to drive nonlinear conversion processes that generate mid-infrared output.    In addition, the Tm:fiber pump laser is designed with novel wavelength diversity that translates to mid-infrared output wavelengths through the freqeuency conversion process while remaining sufficiently spectrally narrow so that the MWIR emission fits within narrow atmospheric transmission bands. A net optical conversion efficiency of 50% from pump to MWIR is anticipated, resulting in >100 W of MWIR power for ~200 W of pump.  This staging, coupled with the high efficiency of the Tm:fiber pump laser, support an architecture with >10% wall-plug efficiency and conformal packaging for small (<3 ft3) volume. The proposed effort focuses on reducing performance risks of the pump laser and parametric converter, anchoring models, and generating a conceptual design for a power-scaled Phase 2 deliverable. The project will be conducted in two six-month phases (Base and Option), taking advantage of Fibertek’s well-equipped facilities, existing material stock, and deep experience in the development of custom, high-peak-power laser sources for DoD applications.