Rapid temperature tuning of a 1.4-mum diode laser with application to high-pressure H(2)O absorption spectroscopy.

Enhanced wavelength tuning of a distributed-feedback InGaAsP diode laser is demonstrated by use of rapid temperature cycling. The laser-active region is cycled from -10 to +50 degrees C (scanning the output from 1399 to 1403 nm) at kilohertz rates by pulsed heating with an auxiliary 532-nm laser. Such 4-nm scans represent a ten-fold increase in the wavelength-scanning range offered by standard current-tuning techniques and thus extend the capabilities of scan-wavelength sensors and systems. As an example application, we demonstrate absorption spectroscopy of H(2)O vapor at a pressure of 10 atm.