Doppler-free two-photon spectroscopy in the vacuum ultraviolet: helium 1(1)S-2(1)S transition

Citation
Sd. Bergeson et al., Doppler-free two-photon spectroscopy in the vacuum ultraviolet: helium 1(1)S-2(1)S transition, J OPT SOC B, 17(9), 2000, pp. 1599-1606
Citations number
37
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Optics & Acoustics
Journal title
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
ISSN journal
0740-3224 → ACNP
Volume
17
Issue
9
Year of publication
2000
Pages
1599 - 1606
Database
ISI
SICI code
0740-3224(200009)17:9<1599:DTSITV>2.0.ZU;2-G
Abstract
We describe techniques for laser spectroscopy in the vacuum-UV (VUV) spectr al region that combine high spectral resolution with high absolute accuracy . A nearly transform-limited nanosecond laser source at 120 nm is construct ed with difference-frequency mixing. This source is used to perform the fir st, to our knowledge, Doppler-free VUV measurement. We measure the inherent ly narrow 1(1)S-2(1)S two-photon transition in atomic helium with a spectra l resolution of 7 parts in 10(8) (180 MHz), the narrowest line width so far observed at such short wavelengths. Careful measurements of optical phase perturbations allow us to determine the absolute frequency of the line cent er to a fractional uncertainty of 1 part in 10(8). Improvements now in prog ress should reduce this uncertainty to 2 parts in 10(9). (C) 2000 Optical S ociety of America [S0740-3224(00)01009-2].