Single AlGaInP Semiconductor Laser Pumped Widely Tunable Mid-IR Generator

Mid-infrared laser sources in the range of 2-5 mm have many important applications such as eye-safe detection, trace-gas monitoring, and wind speed/wind shear measurements. Traditional techniques by optical parametric oscillation (OPO) and dual-laser frequency difference generation require (DFG) high power pump sources and very complex systems. Fabrication of these systems is costly. In this program we propose to develop a single diode-laser pumped mid-IR laser system. The near-IR intermediate output pumped by the 670-nm A1GaInP diode laser mixes with the residual diode laser beam in a quasi-phase matched (QPM) KTA nonlinear crystal and mid-IR signals is generated by intra-cavity QPM-DFG. The mid-IR output can be tuned over a wide range by merely tuning the near-IR; no temperature or angle tuning of the KTA crystal is needed. The tunable mid-IR laser system is all-solid-state, simple, low cost, and highly efficient. Power generation capability are estimated to be hundreds of milliwatt power.| Benefits: Success in this Phase I program will identify the promising concept and provide a viable manufacturing route for practical compact mid-IR laser sources.|