Method for measuring surface potential of the test mass with an optically levitated charged microsphere, Ling-Ling Yang,1 Feng Tang,1 Rui-Jie Li,1 Yan-Jie Zhang,1 Qiang-Bing Mao,2 Hao Xu,3 AND Qing Li1,* Vol. 65, No. 3 / 20 January 2026 / Applied Optics
