JILA, National Institute of Standards and Technology, Boulder, CO, and the University of Colorado, Boulder, CO, USA.
IEEE Trans Ultrason Ferroelectr Freq Control. 2012 Mar;59(3):416-25. doi: 10.1109/TUFFC.2012.2210.
We describe recent experimental progress with the JILA Sr optical frequency standard, which has a systematic uncertainty at the 10-(16) fractional frequency level. An upgraded laser system has recently been constructed in our lab which may allow the JILA Sr standard to reach the standard quantum measurement limit and achieve record levels of stability. To take full advantage of these improvements, it will be necessary to operate a lattice clock with a large number of atoms, and systematic frequency shifts resulting from atomic interactions will become increasingly important. We discuss how collisional frequency shifts can arise in an optical lattice clock employing fermionic atoms and describe a novel method by which such systematic effects can be suppressed.
我们描述了 JILA Sr 光学频率标准的最新实验进展，其系统不确定性在 10-16 分数频率水平。我们实验室最近构建了一个升级后的激光系统，这可能使 JILA Sr 标准达到标准量子测量极限并实现创纪录的稳定水平。为了充分利用这些改进，有必要使用大量原子运行晶格钟，并且原子相互作用引起的系统频率偏移将变得越来越重要。我们讨论了如何在使用费米子原子的光学晶格钟中产生碰撞频率偏移，并描述了一种可以抑制这种系统效应的新方法。
