1. Mid-infrared cavity ring-down spectroscopy using DFB quantum cascade laser with optical feedback for radiocarbon detection
- Author
-
Yuki Okuyama, Norihiko Nishizawa, Hideki Tomita, Masahito Yamanaka, T. Iguchi, Volker Sonnenschein, Ryohei Terabayashi, Shin-ichi Ninomiya, Keisuke Saito, and Kenji Yoshida
- Subjects
Materials science ,Physics and Astronomy (miscellaneous) ,law ,business.industry ,General Engineering ,Mid infrared ,General Physics and Astronomy ,Optoelectronics ,Radiocarbon dating ,Quantum cascade laser ,business ,law.invention ,Cavity ring-down spectroscopy - Abstract
A linewidth reduction of a distributed feedback quantum cascade laser (DFB-QCL) based on optical feedback for a mid-infrared (MIR) cavity ring down spectroscopy (CRDS) 14C spectrometer is presented. A cat-eye reflector as well as a path-length enhancement by a Herriott cell were employed for a compact optical setup. The laser linewidth was evaluated by monitoring the beat frequency between the DFB-QCL and a MIR optical frequency comb (OFC). The linewidth reduction by optical feedback was clearly observed although slow frequency drifts caused by environmental changes were still visible. A low-bandwidth beat-note lock to the OFC was conducted for long-term stabilization as well as for precise frequency scanning and thereby 14C measurement by MIR CRDS with optical feedback was demonstrated successfully.
- Published
- 2020
- Full Text
- View/download PDF