A high stability semiconductor laser system for a ${}^{88}$Sr-based optical lattice clock

Abstract

We describe a frequency stabilized diode laser at 698 nm used for high resolution spectroscopy of the 1S0-3P0 strontium clock transition. For the laser stabilization we use state-of-the-art symmetrically suspended optical cavities optimized for very low thermal noise at room temperature. Two-stage frequency stabilization to high finesse optical cavities results in measured laser frequency noise about a factor of three above the cavity thermal noise between 2 Hz and 11 Hz. With this system, we demonstrate high resolution remote spectroscopy on the 88Sr clock transition by transferring the laser output over a phase-noise-compensated 200 m-long fiber link between two separated laboratories. Our dedicated fiber link ensures a transfer of the optical carrier with frequency stability of 7 \cdot 10^{-18} after 100 s integration time, which could enable the observation of the strontium clock transition with an atomic Q of 10^{14}. Furthermore, with an eye towards the development of transportable optical clocks, we investigate how the complete laser system (laser+optics+cavity) can be influenced by environmental disturbances in terms of both short- and long-term frequency stability.

9 pages, 9 figures, submitted to Appl. Phys. B

References in corpus (10)

• Sr lattice clock at 1x10^{-16} fractional uncertainty by remote optical evaluation with a Ca clock
• Compact, thermal-noise-limited optical cavity for diode laser stabilization at 1 x 10-15
• New Limits on Coupling of Fundamental Constants to Gravity Using ${}^{87}$Sr Optical Lattice Clocks
• Coherent optical phase transfer over a 32-km fiber with 1-s instability at $10^{-17}$
• Probing Interactions between Ultracold Fermions
• Measuring the frequency of a Sr optical lattice clock using a 120-km coherent optical transfer
• An Optical Lattice Clock with Spin-polarized 87Sr Atoms
• Precision frequency measurement of visible intercombination lines of strontium
• Thermal noises and noise compensation in high-reflection multilayer coating
• Optical Interferometers with Reduced Sensitivity to Thermal Noise