Influence of pump intensity on atomic spin relaxation in a vapor cell<xref rid="cpb_28_11_117601fn1" ref-type="fn">*</xref><fn id="cpb_28_11_117601fn1"><label>*</label><p>supported by the National Key R&D Program of China (Grant No. 2017YFA0304502) and the National Natural Science Foundation of China (Grant Nos. 11634008, 11674203, 11574187, and 61227902).</p></fn>

Influence of pump intensity on atomic spin relaxation in a vapor cell**

supported by the National Key R&D Program of China (Grant No. 2017YFA0304502) and the National Natural Science Foundation of China (Grant Nos. 11634008, 11674203, 11574187, and 61227902).

Yang Chen^{1, 2}, Zuo Guan-Hua^{1, 2}, Tian Zhuang-Zhuang^{1, 2}, Zhang Yu-Chi^{3, †}, Zhang Tian-Cai^{1, 2, ‡}

Experimental results for measuring the MRL. (a) MRS for a fixed pump intensity of 0.03 mW/cm². The MRS is shown as the output of the balanced photodetector as a function of the magnetic resonance frequency 2 ω_L = 2 γ B, where γ = 2π × 3.5 Hz/nT for the ground state of the cesium atom. The MRS is fitted by the dispersive Lorentzian shape (blue line, the red line is the experimental result), and the MRL is figured out as Δ ω = 2π × (93.5 ± 0.1) Hz (see the point with a black dotted cycle in (b)). (b) Relation between MRL and pump intensity. The red dots are the experimental results and the solid blue line is the theoretical fitting according to Eq. (12) (see the theoretical discussion below). Nonlinear relation is clearly shown and each data point and the error bar are obtained from five measurements. The best fitting gives the following parameters: α = 2π × (2.1 ± 0.2) × 10³ Hz · cm²/mW and r₀ = 2π × (69.7 ± 4.4) Hz.