Cong Lin, Yuan Zi, Bai Zaiqiao, Wang Xinhe, Zhao Wei, Gao Xinyu, Hu Xiaopeng, Liu Peng, Guo Wanlin, Li Qunqing, Fan Shoushan, Jiang Kaili
State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua-Foxconn Nanotechnology Research Center, Department of Physics, Tsinghua University, Beijing 100084, China.
Department of Physics, Beijing Normal University, Beijing 100875, China.
Sci Adv. 2021 Mar 17;7(12). doi: 10.1126/sciadv.abd2358. Print 2021 Mar.
The torsion balance, consisting of a rigid balance beam suspended by a fine thread, is an ancient scientific instrument, yet it is still a very sensitive force sensor to date. As the force sensitivity is proportional to the lengths of the beam and thread, but inversely proportional to the fourth power of the diameter of the thread, nanomaterials should be ideal building blocks for torsion balances. Here, we report a torsional balance array on a chip with the highest sensitivity level enabled by using a carbon nanotube as the thread and a monolayer graphene coated with Al nanofilms as the beam and mirror. It is demonstrated that the femtonewton force exerted by a weak laser can be easily measured. The balances on the chip should serve as an ideal platform for investigating fundamental interactions up to zeptonewton in accuracy in the near future.
扭秤由一根用细线悬挂的刚性平衡梁组成，是一种古老的科学仪器，但至今仍是一种非常灵敏的力传感器。由于力灵敏度与梁和线的长度成正比，但与线直径的四次方成反比，因此纳米材料应该是扭秤的理想构建块。在此，我们报告了一种芯片上的扭秤阵列，通过使用碳纳米管作为线以及涂覆有铝纳米膜的单层石墨烯作为梁和镜子，实现了最高灵敏度水平。结果表明，弱激光施加的飞牛级力能够轻松被测量。在不久的将来，芯片上的扭秤应该会成为一个理想平台，用于精确研究直至zeptonewton级别的基本相互作用。
