Open AccessCoherent radio-frequency detection for narrowband direct comb spectroscopy
Author(s) -
James Anstie,
Christopher Perrella,
P.S. Light,
André Luiten
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.004088
Subject(s) - narrowband , optics , comb generator , frequency comb , photodiode , materials science , local oscillator , radio frequency , optoelectronics , coherence (philosophical gambling strategy) , spectroscopy , laser , microwave , physics , phase noise , telecommunications , computer science , quantum mechanics
We demonstrate a scheme for coherent narrowband direct optical frequency comb spectroscopy. An extended cavity diode laser is injection locked to a single mode of an optical frequency comb, frequency shifted, and used as a local oscillator to optically down-mix the interrogating comb on a fast photodetector. The high spectral coherence of the injection lock generates a microwave frequency comb at the output of the photodiode with very narrow features, enabling spectral information to be further down-mixed to RF frequencies, allowing optical transmittance and phase to be obtained using electronics commonly found in the lab. We demonstrate two methods for achieving this step: a serial mode-by-mode approach and a parallel dual-comb approach, with the Cs D1 transition at 894 nm as a test case.