PRL 116, 131101 (2016)
New Test of the Gravitational Inverse-Square Law at the Submillimeter Range
with Dual Modulation and Compensation
Wen-Hai Tan, 1 Shan-Qing Yang, 1,* Cheng-Gang Shao, 1 Jia Li, 1 An-Bin Du, 1 Bi-Fu Zhan, 2
Qing-Lan Wang, 3 Peng-Shun Luo, 1 Liang-Cheng Tu, 1 and Jun Luo 1,4,†
1 MOE Key Laboratory of Fundamental Physical Quantities Measurements, School of Physics,
Huazhong University of Science and Technology, Wuhan 430074, People’s Republic of China
2 School of Electrical and Electronic Engineering, Wuhan Polytechnic University, Wuhan 430000, People’s Republic of China
3 School of Science, Hubei University of Automotive Technology, Shiyan 442002, People’s Republic of China
4 Sun Yat-sen University, Guangzhou 510275, People’s Republic of China
(Received 17 August 2015; revised manuscript received 27 January 2016; published 30 March 2016)
By using a torsion pendulum and a rotating eightfold symmetric attractor with dual modulation of both the interested signal and the gravitational calibration signal, a new test of the gravitational inverse-square law at separations down to 295 μm is presented. A dual-compensation design by adding masses on both the pendulum and the attractor was adopted to realize a null experiment. The experimental result shows that, at a 95% confidence level, the gravitational inverse-square law holds (jαj ≤ 1) down to a length scale λ ¼ 59 μm. This work establishes the strongest bound on the magnitude α of Yukawa-type deviations from Newtonian gravity in the range of 70–300 μm, and improves the previous bounds by up to a factor of 2 at the length scale λ ≈ 160 μm.
