Precise measurement of a weak radio frequency electric field using a resonant atomic probe<xref rid="cpb_29_3_033201fn1" ref-type="fn">*</xref><fn id="cpb_29_3_033201fn1"><label>*</label><p>Project supported by the National Key R&D Program of China (Grant No. 2017YFA0304203), the National Natural Science Foundation of China (Grant Nos. 61475090, 61675123, 61775124, and 11804202), the State Key Program of National Natural Science of China (Grant Nos. 11434007 and 61835007), and Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China (Grant No. IRT 17R70).</p></fn>

Precise measurement of a weak radio frequency electric field using a resonant atomic probe**

Project supported by the National Key R&D Program of China (Grant No. 2017YFA0304203), the National Natural Science Foundation of China (Grant Nos. 61475090, 61675123, 61775124, and 11804202), the State Key Program of National Natural Science of China (Grant Nos. 11434007 and 61835007), and Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China (Grant No. IRT 17R70).

Hao Liping¹, Xue Yongmei¹, Fan Jiabei¹, Bai Jingxu¹, Jiao Yuechun^{1, 2}, Zhao Jianming^{1, 2, †}

Measurements of signal electric field, 20 log E_S/E₀), as a function of Δω by changing the signal field frequency for two indicated signal field values E_S = 0.39 V/m (black circles) and 0.07 V/m (red triangles), respectively. Horizontal dot-dashed line displays the idea −3 dB line, related −3 dB bandwidth of 3 MHz, depending on the photodiode used.