Testing the Universality of Free Fall at ${10^{ - 10}}$ level by Comparing the Atoms in Different Hyperfine States with Bragg Diffraction

• DOI: 10.48550/arxiv.1805.07758
• Publication Date: 2018-01-01
• Authors: Zhang, Ke; Zhou, Min-Kang; Cheng, Yuan; Chen, Le-Le; Luo, Qin; Xu, Wen-Jie; Cao, Lu-Shuai; Duan, Xiao-Chun; Hu, Zhong-Kun
• Keywords: Quantum Physics; 0103 physical sciences; FOS: Physical sciences; General Relativity and Quantum Cosmology (gr-qc); Quantum Physics (quant-ph); 01 natural sciences; General Relativity and Quantum Cosmology

We have performed a precision atomic interferometry experiment on testing the universality of free fall (UFF) considering atoms' spin degree of freedom. Our experiment employs the Bragg atom interferometer with $^{87}$Rb atoms either in hyperfine state $\left| {F = 1,{m_F} = 0} \right\rangle $ or $\left| {F = 2,{m_F} = 0} \right\rangle $, and the wave packets in these two states are diffracted in one pair of Bragg beams alternatively, which can help suppress the common-mode systematic errors. We have obtained an E$\rm{\ddot{o}}$tv$\rm{\ddot{o}}$s ratio $��= \left( { 0.9 \pm 2.7} \right) \times {10^{ - 10}}$, and set a new record on the precision with a nearly 5 times improvement. Our experiment gives stronger restrictions on the possible UFF breaking mechanism.