标题： 使用强偏置磁场的光泵浦矢量磁强计 显示英文标题

标题： Optically pumped vector magnetometer using a strong bias magnetic field

摘要： 我们提出一种新方法，使得光学泵浦磁力计（OPM）能够在地球磁场中作为矢量磁力计运行，其敏感轴可以自由定义。 该方法使能够以相同的灵敏度测量地球磁场的任意矢量分量。 OPM 是通过微加工的铯蒸气室与氮缓冲气体实现的，该蒸气室浸入约 730 $\mathrm{\mu T}$的均匀偏置场中。 由于该偏置场比地球磁场强约一个数量级，因此定义了 OPM 的敏感轴。 偏置场由固态磁铁产生，并设计为在蒸气室尺寸内具有非常低的相对不均匀性（相对单位中的$< 10^{-4}$），以及在约 40{\deg }C 处具有零温度依赖性的点。 OPM 利用光窄化效应，即使在如此大的磁场幅度下也能有效抑制自旋交换弛豫。 基于此实现，我们在 100 Hz 至 600 Hz 的区间内展示了低于 60 $\mathrm{fT/\sqrt{Hz}}$的白噪声底限，并具有 $> 2$ kHz 的传感器带宽。 我们的方法实现了无需屏蔽的超灵敏矢量测量能力，这在许多重要应用中都很相关。 显示英文摘要

摘要： We present a novel approach allowing an optically pumped magnetometer (OPM) to be operated within Earth's magnetic field as a vector magnetometer whose sensitive axis can be freely defined. This approach enables the measurement of any vector component of the Earth's magnetic field with the same sensitivity. The OPM is realized by a microfabricated cesium vapor cell with nitrogen buffer gas, which is immersed into a homogeneous bias field of about 730 $\mathrm{\mu T}$. Since this bias field is about one order of magnitude stronger than Earth's magnetic field, it defines the sensitive axis of the OPM. The bias field is generated by solid-state magnets and was designed to exhibit a very low relative inhomogeneity ($< 10^{-4}$ in relative units) within the vapor cell dimensions as well as a point of vanishing temperature dependence at around 40{\deg}C. The OPM utilizes the light narrowing effect, which enables effective suppression of spin-exchange relaxation even in such large magnetic field amplitude. Based on this implementation, we demonstrate a white noise floor of below 60 $\mathrm{fT/\sqrt{Hz}}$ in the interval between 100 Hz and 600 Hz and a sensor bandwidth of $> 2$ kHz. Our approach enables unshielded ultrasensitive vectorial measurement capabilities relevant in many important applications.