Recently, a research team led by Professor Pu Huang and Xi Kong from the School of Physics at Nanjing University, in collaboration with researchers from the University of Science and Technology of China, has made significant progress in the experimental search for dark matter-related new physics.

In this work, the team developed a levitated magnetic force sensor to search for possible weak spin-dependent interactions between electrons at centimeter scales. By exploiting a levitated permanent magnet with a high density of polarized electron spins as both a force sensor and a spin source, the researchers achieved high-precision measurements of extremely weak interactions that may be mediated by hypothetical light bosons associated with dark matter.

The experiment established stringent constraints on two types of spin-spin-velocity-dependent exotic interactions. Compared with previous experimental results, the obtained limits improved by approximately 12 and 13 orders of magnitude in the corresponding interaction ranges, providing new experimental insights into the exploration of dark matter candidates and physics beyond the Standard Model.

The work, entitled “Stringent Constraints on Spin-Spin-Velocity-Dependent Exotic Interactions with a Levitated Magnet Force Sensor,” was published in Physical Review Letters on August 17.

The levitated magnetic sensing platform developed in this study demonstrates the potential of precision force measurements for exploring new fundamental interactions and provides a promising approach for future searches for light bosons and dark matter-related phenomena.

Figure 1. Experimental setup of the levitated magnetic force sensor and rotating spin source.

Publication link: https://journals.aps.org/prl/abstract/10.1103/35c1-ylnx