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arXiv · 1805.07758

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

Ke Zhang·Min-Kang Zhou·Yuan Cheng·Le-Le Chen·Qin Luo·Wen-Jie Xu·Lu-Shuai Cao·Xiao-Chun Duan·Zhong-Kun Hu
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Abstract

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 $\eta = \left( { 0.9 \pm 2.7} \right) \times {10^{ - 10}}$, 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.

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Ke Zhang, Min-Kang Zhou, Yuan Cheng, Le-Le Chen, Qin Luo, Wen-Jie Xu, Lu-Shuai Cao, Xiao-Chun Duan, Zhong-Kun Hu. 2018-05-20. Testing the Universality of Free Fall at ${10^{ - 10}}$ level by Comparing the Atoms in Different Hyperfine States with Bragg Diffraction. https://arxiv.org/abs/1805.07758

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