采用简化的飞行时间荧光成像法测量冷原子样品的等效温度

Effective Temperature Measurement of Cold Atom Sample by Means of the Simplified Time-of-flight Fluorescence Imaging

本文介绍了用于冷原子样品等效温度测量的简化的飞行时间荧光成像法。将用于激光冷却和俘获原子的冷却光,代替标准的飞行时间荧光成像法中额外引入的探测光。在铯原子磁光阱基础上,通过进一步采用偏振梯度冷却技术使冷原子等效温度有效地降低。采用简化的飞行时间荧光成像法测量的铯原子气室磁光阱(光学粘团)的等效温度,典型值为TY≈22.3±2.2μK,TZ≈15.4±2.7μK(TY≈11.6±1.1μK,TZ≈2.8±1.2μK)。本文中的简化飞行时间荧光成像方案,在不牺牲冷原子样品等效温度测量的精度和准确度情况下,更容易在实验中执行和推广,对于应用于冷原子微波原子钟、冷原子光频原子钟、冷原子干涉重力仪等量子精密测量领域,以及采用冷原子样品进一步开展量子光学、量子信息处理等领域的研究工作,具有积极意义和良好的推广价值。

In this paper,a simplified time-of-flight fluorescence imaging method is introduced for measuring the effective temperature of cold atom sample.The cooling laser for laser cooling and trapping atoms instead of the additional probe laser of standard time-of-flight fluorescence imaging.Based on the magneto-optical trap of cesium atom,the effective temperature of cold atoms is effectively reduced by using the technique of polarization gradient cooling.The effective temperature measurement of cesium atomic MOT(molasses)by means of simplified time-of-flight fluorescence imaging,with typical values are TY≈22.3±2.2μK and TZ≈15.4±2.7μK(TY≈11.6±1.1μK and TZ≈2.8±1.2μK).The simplified time-of-flight fluorescence imaging scheme proposed in this paper is easier to execution and promotion in experiments,without sacrificing the precision and accuracy of effective temperature measurement of the cold atom sample.It has positive significance and good promotion value for the application of cold atom microwave atomic clock,cold atom optical frequency atomic clock,cold atom gravimeter and other quantum precision measurement fields,as well as the further development of quantum optics and quantum information processing by using cold atom sample.