Design considerations for a strontium optical frequency standard

摘要

We present the work carried out in the scope of making an optical clock with cold strontium atoms at BNM-SYRTE. To load a magneto-optical trap (MOT), an atomic beam is slowed with a Zeeman slower using the cycling transition ~1S_0→ ~1P_1 at 461 nm. We measured a flux of 2.3 × 10~(11) atoms/s slowed below 50m/s. To generate the 461 nm laser, the frequencies of a Nd:YAG and diodes at 813 nm are summed in a KTP crystal. We obtained 115 mW of blue light corresponding to an efficiency of 2.7 × 10~(-3) W/W~2. We then present the set up used to realize a low frequency noise laser at 689 nm. An extended cavity diode laser is locked to a Fabry-Perot cavity of high finesse. For long term stabilisation, a Ramsey-Borde interferometer will be used.