International comparisons of He-Ne lasers stabilized with¹²⁷I₂at   = 633 nm (July 1993 to September 1995). Part III: Second comparison of Eastern European lasers at   = 633 nm

Abstract

This paper reports the third set of results of a series of grouped laser comparisons from national laboratories undertaken by the Bureau International des Poids et Mesures (BIPM) at the request of the Comité Consultatif pour la Définition du Mètre (CCDM) for the period July 1993 to September 1995. The results of this comparison, involving eight lasers, are comparable with those obtained during a first comparison in 1988 involving most of the same national laboratories. The lasers were first compared with the BIPM lasers with the parameters set to the values normally used in each laboratory, the results then ranged from -23 kHz to +28.2 kHz. After checking and readjusting the values of all the parameters, the range was reduced to -20.4 kHz to +9.7 kHz. Under the latter conditions, the average frequency difference of the group of lasers, with respect to the BIPM4 laser, was -5.8 kHz with a standard uncertainty of 12.3 kHz. Typical frequency stabilities with Allan standard deviations of about 1.8 10 -11 and 1.8 10 -12 were observed with sampling times of 1 s and 100 s, respectively.

International comparisons of He-Ne lasers stabilized with127I2at 633 nm (July 2000). Part X: Comparison of INMETRO (Brazil), INTI (Argentina), NRC-INMS (Canada), CENAM (Mexico), and BIPM lasers at 633 nm

“…This is the tenth in a series of reports describing the results obtained during an extensive programme of laser comparisons carried out over the period July 1993 to March 2001 [1][2][3][4][5][6][7][8][9][10].…”

Frequency Noise Properties of Lasers for Interferometry in Nanometrology

“…L7 is an approximately 25 years old commercial He-Ne laser, where degradation of the laser tube during long time period can be expected. Finally, L8 is He-Ne-I 2 laser—iodine stabilized optical frequency standard for 633 nm [16,17]. …”

Noise Suppression on the Tunable Laser for Precise Cavity Length Displacement Measurement

“…The measurement of displacement of the Fabry-Perot cavities thus could be made by a tunable laser with sub-kHz to sub-MHz linewidth with an optical reference laser with better or similar linewidth [ 9 , 10 ]. The He-Ne lasers can achieve relative stability of [ 11 , 12 , 13 ] but the PZT tuning range is limited only to 1 GHz. Typical diode lasers have larger tuning range but the linewidth of 30 MHz that is suitable only for cavities with very low finesse.…”