We report a new technique for generating magnetic resonance with synchronous modulation of two-photon resonant light fields. Magnetic resonances in fluorescence from a sodium cell are measured to demonstrate suitability of this technique for remote magnetometry. A strong magnetic resonance with its dip corresponding to the Larmor frequency is produced in the presence of a transverse magnetic field. An additional resonance at 3\{Omega_L} is observed, which can be used to determine the magnetic field orientation. We have developed a theoretical model based on the density matrix equations to verify our experimental observations. An average magnetic field sensitivity of 41 \mathbf{pT}/\sqrt{\mathbf{Hz}} is measured using light duty cycles ranging from 35% to 10%. We have discussed possible changes that can be made to improve the sensitivity of this scheme further.

中文翻译：

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使用钠荧光同步调制双光子共振光场的磁力测量

我们报告了一种通过双光子共振光场的同步调制产生磁共振的新技术。测量钠细胞荧光的磁共振以证明该技术适用于远程磁力测定法。在横向磁场存在的情况下会产生强磁共振，其倾角对应于拉莫尔频率。观察到 3\{Omega_L} 处的额外共振，可用于确定磁场方向。我们已经开发了一个基于密度矩阵方程的理论模型来验证我们的实验观察。41 \mathbf{pT}/\sqrt{\mathbf{Hz}} 的平均磁场灵敏度是使用 35% 到 10% 的轻占空比测量的。