High-sensitivity detection of two-photon Ramsey fringes at 30 THz by frequency-comb assisted stimulated emission

Author

Grain, Christophe ; Shelkovnikov, Alexander ; Amy-Klein, Anne ; Butcher, Robert James ; Chardonnet, Christian

Author_Institution

Lab. de Phys. des Lasers, Univ. de Paris-Nord, Villetaneuse, France

Volume

38

Issue

10

fYear

2002

fDate

10/1/2002 12:00:00 AM

Firstpage

1406

Lastpage

1411

Abstract

Spectacular improvements in both resolution and signal-to-noise ratio of two-photon Ramsey fringes obtained at 30 THz have been achieved by implementing a new detection scheme. A molecular beam of SF₆, after passing through the Ramsey regions, is interrogated by a separate laser beam which makes optimal use of the entire Doppler profile by generating a comb of frequencies within a compensated high-finesse cavity. Resulting molecular spectra have the highest resolution ever obtained with CO₂ lasers and, as a standard, the system will soon outperform the best currently available.

Keywords

frequency standards; hyperfine structure; stimulated emission; submillimetre wave spectra; sulphur compounds; time resolved spectra; two-photon spectra; 30 THz; Doppler profile; Fabry-Perot cavity; IR frequency standards; SF₆; compensated high-finesse cavity; frequency metrology; frequency stability; frequency-comb assisted stimulated emission; high-sensitivity detection; hyperfine structure; molecular beam; rovibrational levels; supersonic beam; terahertz detection; two-photon Ramsey fringes; two-photon resonance; ultrahigh resolution molecular spectroscopy; Frequency; Laser stability; Laser theory; Laser transitions; Resonance; Signal resolution; Signal to noise ratio; Stimulated emission; Testing; Ultrafast optics;

fLanguage

English

Journal_Title

Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

0018-9197

Type

jour

DOI

10.1109/JQE.2002.802952

Filename

1035990