Spectroscopic techniques, Semiconductor lasers, Far infrared lasers, Injection lasers, Cavity-ringdown spectroscopy
Continuous wave cavity ringdown spectroscopy requires a rapid termination of the injection of light into the cavity to initiate the decay (i.e., ringdown) event. We demonstrate a technique that accomplishes this through pulsed optical injection of a second laser into the main laser, resulting in 20-100 MHz frequency shifts in the otherwise cavity-locked main laser sufficient to create ringdown events at 3.5 kHz. Data on the frequency shift as a function of both main laser current and relative wavelength are presented, 88 well 88 a demonstration that single exponential decays are maintained in the process.
Greg Bostrom, Andrew Rice, and Dean Atkinson, "Optical injection unlocking for cavity ringdown spectroscopy," Opt. Lett. 39, 4227-4230 (2014) http://www.opticsinfobase.org/ol/abstract.cfm?URI=ol-39-14-4227