Long-Sheng Ma 1,3, Susanne Picard 1, Massimo Zucco 1,4, Jean-Marie Chartier 1, Lennart Robertsson 1,5 and Robert S Windeler 2
1
Bureau International des Poids et Mesures, Pavillon de Breteuil, F-92312 Sevres Cedex, France
2
OFS Laboratories, 600 Mountain Ave, Murray Hill, NJ 07974, USA
3
Permanent address: Physics Department, East China Normal University, Shanghai 200062, People's Republic of China.
4
On leave from Consiglio Nazionale delle Ricerche—Istituto di Metrologia 'Gustavo Colonnetti', Strade delle Cacce 73, 10135 Turin, Italy.
5
Author to whom any correspondence should be addressed.
Long-Sheng Ma et al 2004 Metrologia 41 65
Direct phase-coherent measurements of the absolute frequency of the 11-5, R(127) transition in 127I2 at 633 nm of the BIPM4 He–Ne laser have been made. This laser has been used as a reference laser for a large number of international comparisons over the years and, as such, has served as the connecting point for the national implementation of the SI metre in the member states of the Metre Convention. The frequency value found for the f-component was 473 612 353 605.4 kHz with a combined uncertainty of 1.8 kHz, a value in close agreement with the value adopted for this radiation in the list of recommended radiations for the realization of the metre, which is 473 612 353 604 kHz.
42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.60.Lh Efficiency, stability, gain, and other operational parameters
42.65.Re Ultrafast processes; optical pulse generation and pulse compression
42.60.Jf Beam characteristics: profile, intensity, and power; spatial pattern formation
Issue 1 (February 2004)
Received 22 July 2003
Published 16 December 2003
Long-Sheng Ma et al 2004 Metrologia 41 65
M J van de Sande and J J A M van der Mullen 2002 J. Phys. D: Appl. Phys. 35 1381
Masatake Yamaguchi et al 2004 J. Phys.: Condens. Matter 16 3933