增强型原子磁力测量：利用挤压自旋态
Enhanced Atomic Magnetometry with a Pinched Spin State
- Fudan University（复旦大学）
- Institute of Modern Physics, Fudan University（复旦大学现代物理研究所）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
该研究利用挤压自旋态增强原子磁力计的量子Fisher信息，通过对称频谱设计实现磁场响应增强，在紧凑多程池中实现高灵敏度双轴零场磁力计。
AI中文摘要：
原子自旋传感器的灵敏度从根本上受限于探针态的量子Fisher信息（QFI）。挤压态$|{F,0}\rangle$在横向场传感中的单粒子QFI比拉伸态$|{F,F}\rangle$大$(F+1)$倍，对应自旋投影噪声限制的场不确定度预计降低$\sqrt{F+1}$倍。我们证明，通过设计关于$m=0$对称的频谱，可以在射频传感方案中利用这一优势，实现理想的$(F+1)$倍磁场响应增强。对于$F=2$的$^{87}\mathrm{Rb}$，我们观察到高达2.7倍的响应增强。将该方法应用于紧凑的$0.8~\mathrm{cm}^3$抗弛豫涂层多程池中，我们实现了一种单光束、双轴、零场磁力计，在室温下于$3$--$100$~Hz频率范围内达到$13$--$23~\mathrm{fT}/\sqrt{\mathrm{Hz}}$的灵敏度。
英文摘要：
The sensitivity of an atomic spin sensor is fundamentally constrained by the quantum Fisher information (QFI) of the probe state. The pinched state, $|{F,0}\rangle$, has an $(F+1)$-fold larger single-particle QFI for transverse-field sensing than the stretched state, $|{F,F}\rangle$, corresponding to a predicted $\sqrt{F+1}$ reduction in the spin-projection-noise-limited field uncertainty. We show that this advantage can be accessed in an rf sensing scheme by engineering a spectrum symmetric about $m=0$, yielding an ideal $(F+1)$-fold enhancement of magnetic-field response. For $^{87}\mathrm{Rb}$ with $F=2$, we observe up to 2.7-fold response enhancement. Implementing this approach in a compact $0.8~\mathrm{cm}^3$ anti-relaxation-coated multipass cell, we realize a single-beam, dual-axis, zero-field magnetometer, achieving $13$--$23$~$\mathrm{fT}/\sqrt{\mathrm{Hz}}$ over $3$--$100$~Hz at room temperature.
