Broadband Fourier-transform spectrometer enabling modal subset identification in Fabry-Pérot-based astrocombs.
Opt Express
; 25(16): 19251-19262, 2017 Aug 07.
Article
em En
| MEDLINE
| ID: mdl-29041118
ABSTRACT
A multi-GHz frequency comb (astrocomb) is typically realized by filtering modes of a sub-GHz frequency comb (source comb) in a Fabry-Pérot etalon, which can lead to ambiguities in determining which subset of source comb modes has been filtered. Here we demonstrate a broadband Fourier-transform spectrometer (FTS) with a resolving power of R = 430,000 at 550 nm, and apply it to the identification of comb subsets from a filtered 1GHz supercontinuum. After apodization the FTS demonstrated an instrument line shape width of 1.26 GHz which enabled individual comb-line positions to be identified with an uncertainty of 17.6 MHz, a relative precision of 5 × 10-8. Correcting for air dispersion allowed the instrument to determine the comb-mode spacing to an accuracy of 300 Hz and filtered subsets of source comb modes to be uniquely distingished across the entire comb bandwidth from 550 to 900 nm. The inherently broadband design of the FTS makes it suitable in future applications for calibrating ultra-broadband astrocombs employed by instruments such as ELT HIRES.
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1
Base de dados:
MEDLINE
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Revista:
Opt Express
Assunto da revista:
OFTALMOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article