论文标题
近地面钻孔中的磁光诱捕
Magneto-optical trapping in a near-surface borehole
论文作者
论文摘要
钻孔重力传感可用于许多应用中，以测量孔周围的特征，包括岩石型变化映射和储层孔隙率的测定。基于原子干涉法的量子技术重力传感器具有提高的调查速度和校准需求减少的能力。尽管在现实世界环境中已经证明了表面传感器，但需要在钻孔中部署此类设备的鲁棒性和减少对径向尺寸，重量和功耗的大幅改善。为了实现朝下钻孔的冷原子传感器部署的第一步，我们展示了一个可钻孔可驱动的磁磁陷阱，这是许多基于冷原子的系统的核心包装。包含磁光陷阱本身的外壳本身的外部半径为（$ 60 \ pm0.1 $）毫米的最宽点，长度为（$ 890 \ pm5 $）毫米。该系统用于在14 cm宽的50 m深钻孔中以1 m的间隔生成原子云，以模拟井内重力调查。在调查过程中，平均云生成的系统（3.0 $ \ pm 0.1）\ times 10^{5} $ $^{87} $ rb原子，在调查中，原子编号的标准偏差为$ 9 \ $ 9 \ times 10^{4} $。
Borehole gravity sensing can be used in a number of applications to measure features around a well including rock-type change mapping and determination of reservoir porosity. Quantum technology gravity sensors based on atom interferometry have the ability to offer increased survey speeds and reduced need for calibration. While surface sensors have been demonstrated in real world environments, significant improvements in robustness and reductions to radial size, weight, and power consumption are required for such devices to be deployed in boreholes. To realise the first step towards the deployment of cold atom-based sensors down boreholes, we demonstrate a borehole-deployable magneto-optical trap, the core package of many cold atom-based systems. The enclosure containing the magneto-optical trap itself had an outer radius of ($60\pm0.1$) mm at its widest point and a length of ($890\pm5$) mm. This system was used to generate atom clouds at 1 m intervals in a 14 cm wide, 50 m deep borehole, to simulate an in-borehole gravity surveys are performed. During the survey the system generated on average clouds of (3.0 $\pm 0.1) \times 10^{5}$ $^{87}$Rb atoms with the standard deviation in atom number across the survey observed to be as low as $9 \times 10^{4}$.
