A simple rapid thermal length control for lasers and etalons

Frequency stabilization of a He-Ne laser using lateral stress

Frequency stabilization of an internal mirror He-Ne laser by a new simple method is reported. In this method, the laser cavity length is modulated by stretching the front part of the laser tube using lateral stress; in this way the laser cavity length is stabilized on the Lamb dip. The relative frequency stability is +/-4.1 x 10(-9) over 1 h or longer.

Stabilized (3)He-(20)Ne transverse Zeeman laser

Tuning characteristics of power, intramode beat frequency, and polarization of 633-nm internal mirror lasers filled with natural Ne or (20)Ne are studied. It is found that the tuning curve of a polarization signal is S-shaped for the natural Ne laser, whereas that of the intramode beat frequency is S-shaped for the (20)Ne laser. The characteristic parameters of the tuning curve of the intramode beat frequency are determined. The axial modes of a (3)He-(20)Ne laser are collapsed into one by a transverse magnetic field and frequency stabilized by cooling the laser tube with a fan to keep the intramode beat constant. Frequency fluctuation of 3 x 10(-10) is obtained by the Allan variance analysis for the integration period range of 0.1-100 sec. Absolute accuracy and interinstrumental reproducibility of stabilized wavelengths can be expected for a (3) He-(20)Ne transverse Zeeman laser stabilized at the central frequency of the intramode beat.