Iodine-stabilized He-Ne laser pumped by transverse rf-discharge

Abstract

The results of experimental investigations of He-Ne/ 127 I 2 lasers (λ = 633 nm) pumped by transverse rf-discharge are presented. Due to the low level of amplitude fluctuations, the frequency stability of such lasers reaches 5⋅10-13 for the integration time 100 s, and it is about six times as large as the stability of the lasers pumped by dc-discharge. The modulation shifts of the frequency of stabilized He-Ne/ 127 I 2 lasers were measured with high accuracy in the wide range of the frequency deviation 1.5 MHz ≤ D ≤ 20 MHz. The sources of the asymmetry of saturated-absorption resonances were determined as the joint action of the lenslike properties of the absorption medium and the elastic velocity-changing collisions of absorbing molecules. The results of a bilateral laser frequency comparison of the developed laser and the laser DE-3 (KIM, Kharkiv) are reported.

Design and testing of iodine cells for metrological laser application

“…It is known that the hyperfine frequency is influenced by some effects: amplitude of laser frequency modulation, iodine pressure, laser intracavity power [3], wavefront geometry [4], gas lens effects [5,6], elastic velocitychanging collisions effect [7,8], contamination of the reference gas [9], etc. Among of main factors defining the net error budget of stabilized laser frequency are uncertainties connected with iodine absorption cell: iodine purity uncertainty 5 kHz, cold-finger temperature 2.5 kHz.…”