학술논문

Multifrequency Heterodyne Detection of Molecules Using a Hot Electron Bolometer Mixer pumped by Two Phase-Locked THz-Quantum Cascade Lasers
Document Type
Periodical
Source
IEEE Transactions on Terahertz Science and Technology IEEE Trans. THz Sci. Technol. Terahertz Science and Technology, IEEE Transactions on. 10(5):474-479 Sep, 2020
Subject
Fields, Waves and Electromagnetics
Temperature measurement
Frequency measurement
Mixers
Receivers
Quantum cascade lasers
Atmospheric measurements
Extraterrestrial measurements
Gas cell measurement
hot electron bolometer mixer (HEBM)
low-noise heterodyne receiver
phase-locking
terahertz quantum cascade laser (THz-QCL)
Language
ISSN
2156-342X
2156-3446
Abstract
We have successfully demonstrated the simultaneous phase-locking of two terahertz quantum cascade lasers (THz-QCLs). These phase-locked THz-QCLs are used as local oscillators of a hot electron bolometer mixer (HEBM). The HEBM was simultaneously pumped by two phase-locked THz-QCLs for the multifrequency heterodyne detection of emission line spectra of methanol [CH 3 OH] at 2 THz using a gas cell. The phase-locking of THz-QCLs with arbitrary frequencies using an optical comb and a photomixer to generate THz references was also demonstrated. An advantage of this technique is that it expands the RF bandwidth of an HEBM.