Modulation transfer spectroscopy based on acousto-optic modulator with zero frequency shift<xref rid="cpb_27_11_114203fn1" ref-type="fn">*</xref> <fn id="cpb_27_11_114203fn1"> <label>*</label> <p>Project supported by the National Key Research and Development Program of China (Grant No. 2016YFA0302101), the Foundation of China Academy of Space Technology, and the Initiative Program of State Key Laboratory of Precision Measurement Technology and Instruments, China.</p> </fn>

Modulation transfer spectroscopy based on acousto-optic modulator with zero frequency shift* *

Project supported by the National Key Research and Development Program of China (Grant No. 2016YFA0302101), the Foundation of China Academy of Space Technology, and the Initiative Program of State Key Laboratory of Precision Measurement Technology and Instruments, China.

Wu Chen-Fei^{1, 2}, Yan Xue-Shu^{2, 3}, Wei Li-Xun⁴, Ma Pei⁴, Tu Jian-Hui⁴, Zhang Jian-Wei^{2, 3, †}, Wang Li-Jun^{1, 2, 3, ‡}

(a) SAS signal and MTS signal for |6²S_1/2, F = 4⟩ → |6²P_3/2, F′⟩ transitions at a modulation frequency of 3.6 MHz. Zero frequency corresponds to |6²S_1/2, F = 4⟩ → |6²P_3/2, F′ = 5⟩ cycling transition. (b) Beat note signals between the negative 80 MHz frequency shift probe beam and the modulated pump beam to monitor the pump beam frequency.