Absolute frequency stabilization of an extended-cavity diode laser against Doppler-free H_(2)~(17)O absorption lines at 1.384 (mu)m

摘要

We report the frequency stabilization of a cw extended-cavity diode laser against saturated absorption lines of the H_(2)~(17)O isotopologue of water vapor at around 1.384 (mu)m. The saturation of rotovibrational transitions is achieved by filling a high-finesse optical resonator with H_(2)~(17)O at low pressure and by locking the laser frequency to the resonator by using the Pound-Drever-Hall technique. Absolute frequency stabilization is obtained, locking the cavity resonance to the center of the sub-Doppler line by means of the wavelength modulation method. A relative frequency stability of (sigma)_(y)(tau) velence 10~(-13)(0.1(tau)~(-2) + 0.9)~(1/2) is demonstrated for integration times in the range 4 ms < tau< 30 s.