title: Laser-Frequency Stabilization Based on Steady-State Spectral-Hole Burning in Eu(3+)∶Y(2)SiO(5).
abstract: We present and analyze a method of laser-frequency stabilization via steady-state patterns of spectral holes in Eu(3+)∶Y(2)SiO(5). Three regions of spectral holes are created, spaced in frequency by the ground-state hyperfine splittings of (151)Eu(3+). The absorption pattern is shown not to degrade after days of laser-frequency stabilization. An optical frequency comparison of a laser locked to such a steady-state spectral-hole pattern with an independent cavity-stabilized laser and a Yb optical lattice clock demonstrates a spectral-hole fractional frequency instability of 1.0×10(-15)τ(-1/2) that averages to 8.5(-1.8)(+4.8)×10(-17) at τ=73  s. Residual amplitude modulation at the frequency of the rf drive applied to the fiber-coupled electro-optic modulator is reduced to less than 1×10(-6) fractional amplitude modulation at τ>1  s by an active servo. The contribution of residual amplitude modulation to the laser-frequency instability is further reduced by digital division of the transmission and incident photodetector signals to less than 1×10(-16) at τ>1  s.
authors.affiliation: National Institute of Standards and Technology, 325 Broadway Street, Boulder, Colorado 80305, USA.
authors.forename: Shon
authors.initials: S
authors.lastname: Cook
authors.affiliation: National Institute of Standards and Technology, 325 Broadway Street, Boulder, Colorado 80305, USA.
authors.forename: Till
authors.initials: T
authors.lastname: Rosenband
authors.affiliation: National Institute of Standards and Technology, 325 Broadway Street, Boulder, Colorado 80305, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Leibrandt