Near-Field GHz Rotation and Sensing with an Optically Levitated Nanodumbbell

Peng Ju, Yuanbin Jin, Kunhong Shen, Yao Duan, Zhujing Xu, Xingyu Gao, Xingjie Ni, Tongcang Li

Research output: Contribution to journalArticlepeer-review

2 Scopus citations


A levitated nonspherical nanoparticle in a vacuum is ideal for studying quantum rotations and is an ultrasensitive torque detector for probing fundamental particle-surface interactions. Here, we optically levitate a silica nanodumbbell in a vacuum at 430 nm away from a sapphire surface and drive it to rotate at GHz frequencies. The relative linear speed between the tip of the nanodumbbell and the surface reaches 1.4 km s-1 at a submicrometer separation. The rotating nanodumbbell near the surface demonstrates a torque sensitivity of (5.0 ± 1.1) × 10-26 N m Hz-1/2 at room temperature. Moreover, we probed the near-field laser intensity distribution beyond the optical diffraction limit with a nanodumbbell levitated near a nanograting. Our numerical simulations show that the system can measure the Casimir torque and will improve the detection limit of non-Newtonian gravity by several orders of magnitude.

Original languageEnglish (US)
Pages (from-to)10157-10163
Number of pages7
JournalNano letters
Issue number22
StatePublished - Nov 22 2023

All Science Journal Classification (ASJC) codes

  • Bioengineering
  • General Chemistry
  • General Materials Science
  • Condensed Matter Physics
  • Mechanical Engineering

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