Zhao Qilai, Zhou Kaijun, Wu Zisheng, Yang Changsheng, Feng Zhouming, Cheng Huihui, Gan Jiulin, Peng Mingying, Yang Zhongmin, Xu Shanhui
Opt Lett. 2018 Jan 1;43(1):42-45. doi: 10.1364/OL.43.000042.
The Earth's magnetic field has significant effects that protect us from cosmic radiation and provide navigation for biological migration. However, slow temporal variations originating in the liquid outer core invariably exist. To understand the working mechanism of the geomagnetic field and improve accuracy of navigation systems, a high-precision magnetometer is essential to measure the absolute magnetic field. A helium optically pumping magnetometer is an advanced approach, but its sensitivity and accuracy are directly limited by the low-frequency relative intensity noise and frequency stability characteristics of a light source. Here, we demonstrate a near quantum-noise limited and absolute frequency stabilized 1083 nm single-frequency fiber laser. The relative intensity noise is only 5 dB higher than the quantum-noise limit, and the root mean square of frequency fluctuation is ∼17 kHz after locked. This fiber laser could suppress the fluctuation of magnetic resonant frequency and improve the signal-to-noise ratio of the magnetic resonance signal detection.
地球磁场具有显著影响，它保护我们免受宇宙辐射，并为生物迁徙提供导航。然而，源自液态外核的缓慢时间变化总是存在的。为了理解地磁场的工作机制并提高导航系统的精度，高精度磁力计对于测量绝对磁场至关重要。氦光泵磁力计是一种先进的方法，但其灵敏度和精度直接受到光源低频相对强度噪声和频率稳定性特性的限制。在此，我们展示了一种接近量子噪声极限且绝对频率稳定的1083纳米单频光纤激光器。相对强度噪声仅比量子噪声极限高5分贝，锁定后频率波动的均方根约为17千赫兹。这种光纤激光器可以抑制磁共振频率的波动，并提高磁共振信号检测的信噪比。
