Semiconductor Laser for the 2-5 Micrometers and 7-9 Micrometers Region/ Quantum Cascade Lasers

摘要

The quantum cascade laser is one of the strong candidates for a portable mid-infrared light source for a variety of DoD applications We have seen dramatic improvements in high temperature performance at long wavelengths, including threshold current densities as low as 1.4 kA/cm(2) and peak power outputs greater than 7 W for a single 20 mm aperture. Along with the significant design improvements, we have also demonstrated laser operation at 9 and 11 mm up to 425 K. Single mode operation has been accomplished with the use of surface distributed feedback gratings. An important parallel development to these performance improvements is the integration of discrete lasers into a compact, durable laser pointer system. A compact, battery-driven power supply has been designed and tested, as well as a simple, laboratory optical system for pointer evaluation.