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arXiv · 2104.10026

Super-resolved imaging of a single cold atom on a nanosecond timescale

Zhong-Hua Qian·Jin-Ming Cui·Xi-Wang Luo·Yong-Xiang Zheng·Yun-Feng Huang·Ming-Zhong Ai·Ran He·Chuan-Feng Li·Guang-Can Guo
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Abstract

In cold atomic systems, fast and high-resolution microscopy of individual atoms is crucial, since it can provide direct information on the dynamics and correlations of the system. Here, we demonstrate nanosecond-scale two-dimensional stroboscopic pictures of a single trapped ion beyond the optical diffraction limit, by combining the main idea of ground-state depletion microscopy with quantum state transition control in cold atoms. We achieve a spatial resolution up to 175~nm using an NA = 0.1 objective in the experiment, which represents a more than tenfold improvement compared with direct fluorescence imaging. To show the potential of this method, we apply it to observe the secular motion of the trapped ion, we demonstrate a temporal resolution up to 50~ns with a displacement detection sensitivity of 10~nm. Our method provides a powerful tool for probing particle positions, momenta, and correlations, as well as their dynamics in cold atomic systems.

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Zhong-Hua Qian, Jin-Ming Cui, Xi-Wang Luo, Yong-Xiang Zheng, Yun-Feng Huang, Ming-Zhong Ai, Ran He, Chuan-Feng Li, Guang-Can Guo. 2021-11-22. Super-resolved imaging of a single cold atom on a nanosecond timescale. https://doi.org/10.1103/physrevlett.127.263603

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