Ma Ning, Fang Xiujie, Zhang Yaqi, Xing Bozheng, Duan Lihong, Lu Jixi, Han Bangcheng, Ma Danyue
Opt Express. 2024 Sep 9;32(19):33378-33390. doi: 10.1364/OE.530764.
An optical pumping scheme is proposed for reducing the gradient of electron spin polarization and suppressing light source noise in a spin-exchange relaxation-free magnetometer. This is achieved by modulating only the phase of a narrow-linewidth pump light field with external Gaussian noise. Compared to the absence of phase modulation, the uniformity of electron spin polarization was improved by over 40%, and the light-frequency noise suppression ratio of the magnetometer was enhanced by 4.3 times. Additionally, the response of the magnetometer was increased by 54%, resulting in a sensitivity of 0.34 fT/Hz at 30 Hz. The applicability of this scheme can extend to other optical pumping experiments involving large atom ensembles requiring uniform electron spin polarization distribution, which is beneficial for developing ultra-high sensitivity and high stability magnetometers essential for magneto-cardiography and magneto-encephalography research applications.
提出了一种光抽运方案，用于降低无自旋交换弛豫磁力计中电子自旋极化的梯度并抑制光源噪声。这是通过用外部高斯噪声仅调制窄线宽泵浦光场的相位来实现的。与未进行相位调制相比，电子自旋极化的均匀性提高了40%以上，磁力计的光频噪声抑制比提高了4.3倍。此外，磁力计的响应提高了54%，在30 Hz时灵敏度达到0.34 fT/Hz。该方案的适用性可扩展到其他涉及需要均匀电子自旋极化分布的大原子系综的光抽运实验，这有利于开发对心磁图和脑磁图研究应用至关重要的超高灵敏度和高稳定性磁力计。
