线形离子阱杂散电场漂移的测量与优化

Measurement and optimization of stray electric field shifts of linear ion trap

在光频标的实验中,射频场所引入的微运动会对系统频率测量产生很大的误差。即使在实验前将微运动补偿至最佳状态,但实验过程中随着杂散电场的漂移,微运动的影响又会逐渐显现,需要不断地补偿才能减小其影响。针对该问题,在线形离子阱系统中利用氧化铟锡导电玻璃对真空系统进行优化,以抑制离子阱杂散电场的漂移。通过测量和计算得出优化后杂散电场漂移值为1.63µV·m^(−1)·s^(−1),约为优化前结果57.7µV·m^(−1)·s^(−1)的1/40,使得在长时间实验的过程中微运动的影响可以忽略不计,实验的有效时间得以显著增加。

Micromotion induced by radio-frequency(RF)field contributes greatly to the systematic frequency shifts of optical frequency standards(OFSs).Although the micromotion is compensated to the best degree before each experiment,the influence of micromotion will gradually appear with the shift of stray electric field during the experiment,which requires continuous compensation.To overcome this problem,indium tin oxide(ITO)conductive glass is used to optimize the vacuum system in linear ion trap system to restrain the shift of stray electric field.By measuring and calculating,the stray electric field shift is minimized to 1.63µV·m^(−1)·s^(−1),after optimization,which is around 1/40 of the previous work 57.7µV·m^(−1)·s^(−1),so that the influence of micromotion can be negligible during the long-time experiment,and the effective time of experiment can be significantly increased.