A diode-pumped broadband multiple-quantum-well vertical-external-cavity surface-emitting semiconductor laser has been developed for high-sensitivity intracavity laser-absorption spectroscopy. The semiconductor structure design has been optimized so as to provide maximum laser-emission bandwidth and wavelength tunability. The laser has a 100-mW threshold of continuous room-temperature operation, and it can be tuned within 25 nm around its design wavelength (980 nm). A detection limit lower than 10<sup>−10</sup> per centimeter of absorption path has been achieved, given ∼3×10<sup>−11</sup> cm<sup>−1</sup> Hz<sup>−1/2</sup>. Its spectro-temporal dynamics has been studied in the time range from a few microseconds to ∼1 s. No evidence of nonlinear mode interactions, which in many cases limit the sensitivity, has been observed. We have also shown that with a cavity length reduced to 2.5 cm, the laser is very attractive as a tunable single-frequency source owing to its stable operation in a single TEM<sub>00</sub> mode at a pump power of up to 1 W.
© 2000 Optical Society of America
(120.6200) Instrumentation, measurement, and metrology : Spectrometers and spectroscopic instrumentation
(140.3480) Lasers and laser optics : Lasers, diode-pumped
(140.3570) Lasers and laser optics : Lasers, single-mode
(140.3600) Lasers and laser optics : Lasers, tunable
(250.7260) Optoelectronics : Vertical cavity surface emitting lasers
A. Garnache, A. A. Kachanov, F. Stoeckel, and R. Houdré, "Diode-pumped broadband vertical-external-cavity surface-emitting semiconductor laser applied to high-sensitivity intracavity absorption spectroscopy," J. Opt. Soc. Am. B 17, 1589-1598 (2000)