Temperature-insensitive laser frequency stabilization to molecular absorption edge using an acousto-optic modulator.

ABSTRACT

A temperature-insensitive edge laser frequency stabilization method with an acousto-optic modulator (AOM) was proposed and demonstrated both theoretically and experimentally in this Letter. In the method, in addition to the unshifted laser frequency, two other shifted frequencies were generated by the AOM. The intensity ratio of these two shifted frequencies was used to stabilize the laser. As the intensity ratio was nearly constant despite the temperature change, the proposed method was temperature insensitive. The theoretical and experimental results showed that the frequency drift of a stabilized laser induced by temperature change was reduced by more than 2 orders of magnitude by using the proposed method when compared with traditional frequency stabilization without an AOM.