High-Q resonant cavities for terahertz quantum cascade lasers |
Optics Express, Vol. 23, Issue 3, pp. 3751-3761 (2015)
http://dx.doi.org/10.1364/OE.23.003751
http://dx.doi.org/10.1364/OE.23.003751
We report on the realization and characterization of two different designs for resonant THz cavities, based on wire-grid polarizers as input/output couplers, and injected by a continuous-wave quantum cascade laser (QCL) emitting at 2.55 THz. A comparison between the measured resonators parameters and the expected theoretical values is reported. With achieved quality factor Q ≈ 2.5 × 105, these cavities show resonant peaks as narrow as few MHz, comparable with the typical Doppler linewidth of THz molecular transitions and slightly broader than the free-running QCL emission spectrum. The effects of the optical feedback from one cavity to the QCL are examined by using the other cavity as a frequency reference.
© 2015 Optical Society of America
No comments:
Post a Comment
Please share your thoughts. Leave a comment.