Stabilization of a laser on a large-detuned atomic-reference frequency by resonant interferometry

Abstract

Abstract. We report a simple technique for stabilization of a laser frequency at the wings of an atomic resonance. The reference signal used for stabilization issues from interference effects obtained in a low-quality cavity filled with a resonant atomic vapour. For a frequency detuned at 2.6 GHz from the 133 Cs D 2 6S 1/2 F=4 to 6P 3/2 F'= 5 transition, the fractional frequency Allan deviation is 10 −8 for averaging times of 300 s, corresponding to a frequency deviation of 4 MHz. Adequate choice of the atomic density and of the cell thickness allows locking the laser at detunings larger than 10 GHz. Such a simple technique does not require magnetic fields or signal modulation.

Determination of atomic density and collisional broadening of an alkali vapor by resonant interferometry

“…Density determination can also be improved by increasing the fringe contrast by using higher reflectance windows (as sapphire windows) [13] or even placing the vapor inside a FP interferometer [14]. For thicker cells the distance between two maxima gets smaller which may favor the use of the proposed technique for lower vapor densities.…”

“…In this article, we describe a technique that allows to measure the atomic density and the collisional broadening rate independently. The technique is based on interferometry of the multiple reflected beams from the windows of a cell containing atomic vapor [13,14]. The frequency of the maxima of the interferometric fringes at the resonance wings is determined by the frequency dependent refractive index that is very sensitive to atomic densities changes but depends weakly on collisional broadening.…”

Low-drift Zeeman shifted atomic frequency reference

“…A common approach is to use a second laser which is referenced, or slaved, in some way to a laser that is stabilized to an atomic transition. Often this is achieved via a stabilized cavity [13][14][15]. Also, one can perform a beat measurement between the slave and reference lasers and stabilize the frequency difference between them [16,17] or apply a sideband to the light using an electro-optic modulator (EOM) and seed the slave with the sideband [18,19].…”