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

TL;DR

This paper presents a novel super-resolution microscopy technique for cold atoms that achieves nanosecond temporal resolution and sub-200 nm spatial resolution, enabling detailed observation of atomic dynamics.

Contribution

It introduces a method combining ground-state depletion microscopy with quantum state control to image single cold atoms at nanosecond timescales with high spatial resolution.

Findings

Achieved 175 nm spatial resolution beyond diffraction limit.

Demonstrated 50 ns temporal resolution in imaging.

Observed secular motion of a trapped ion with high sensitivity.

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.