High-performance GaSb laser diodes and diode arrays in the 2.1-3.3 micron wavelength range for sensing and defense applications

Mid-infrared spectral region (2-4 μm) is gaining significant attention recently due to the presence of numerous enabling applications in the field of gas sensing, medical, and defense applications. Gas sensing in this spectral region is attractive due to the presence of numerous absorption lines for such gases as methane, ethane, ozone, carbon dioxide, carbon monoxide, etc. Sensing of the mentioned gas species is of particular importance for applications such as atmospheric LIDAR, petrochemical industry, greenhouse gas monitoring, etc. Defense applications benefit from the presence of covert atmospheric transmission window in the 2.1-2.3 micron band which is more eye-safe and offers less Rayleigh scattering than the conventional atmospheric windows in the near-infrared. Major requirement to enable these application is the availability of high-performance, continuous-wave laser sources in this window. Type-I GaSb-based laser diodes are ideal candidates for these applications as they offer direct emission possibility, high-gain and continuous wave operation. Moreover, due to the nature of type-I transition, these devices have a characteristic low operation voltage, which results in very low input powers and high wall-plug efficiency. In this work, we present recent results of 2 μm – 3.0 μm wavelength room-temperature CW light sources based on type-I GaSb developed at Brolis Semiconductors. We discuss performance of defense oriented high-power multimode laser diodes with < 1 W CW power output with over 30 % WPE as well as ~ 100 mW single TE00 Fabry-Perot chips. In addition, recent development efforts on sensing oriented broad gain superluminescent gain chips will be presented.