Tunable Diode Lasers (TDL) for Spectroscopy and Environmental Monitoring
نویسنده
چکیده
The current status of III-V tunable diode lasers (TDLs) emitting between 1 -5pm wavelengths for spectroscopy and chemical analysis is described. Single mode distributed feedback (DFB) strained layer lnGaAs(P) lasers grown on lnP substrates with emission wavelength from 1.2 to 2.06 pm have been developed at JPL. DFB ridge waveguide lasers at 2,06pm have operated continuous wave (CW) up to 50°C with output power of more than 10 mW and excellent reliability. Space qualified tunable diode lasers have been developed for planetary atmospheric studies for the first time. TDLs at the wavelengths of 1.37 pm, 1.43 ~m, and 2.04 pm for the detection of water, carbon dioxide and their isotopes have been fabricated for implementation in the Mars Volatiles and Climate Surveyor (MVACS) instrument as part of Mars ’98 flight. The performance of antimonide-based quantum well lasers emitting in the 2 to 5 pm has improved significantly in recent years. Pulsed performance at temperatures over 200”K and CW performance over 150”K has been reported at wavelengths over 3 pm by several laboratories, Further reduction of the non-radiative Auger recombination to improve the CW operation of the antimonide-based lasers at higher temperatures is currently under investigation by several groups.
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