Mid-infrared III-V diode lasers for trace-gas sensing

Semiconductor diode lasers are well-suited as sources for trace-gas monitoring systems using laser absorption spectroscopy (LAS). They are compact, and as single-mode, distributed feedback (DFB) lasers, their wavelengths tune continuously and accurately with current and temperature. In the near-infrared from about 1.25 to 2 /spl mu/m, diode lasers with wavelengths corresponding to the molecular absorption lines are commercially available.