The intrinsic frequency fluctuations of two single-mode quantum cascade (QC) distributed-feedback lasers operating continuously at a wavelength of 8.5 μm are reported. A Doppler-limited rovibrational resonance of nitrous oxide is used to transform the frequency noise into measurable intensity fluctuations. The QC lasers, along with recently improved current controllers, exhibit a free-running frequency stability of 150 kHz over a 15-ms time interval.
© 2002 Optical Society of America
[Optical Society of America ]
T. L. Myers, R. M. Williams, M. S. Taubman, C. Gmachl, F. Capasso, D. L. Sivco, J. N. Baillargeon, and A. Y. Cho, "Free-running frequency stability of mid-infrared quantum cascade lasers," Opt. Lett. 27, 170-172 (2002)