High performance imaging of $^{171}$Yb atom in shallow clock-magic tweezer by alternating dual-tone narrowline cooling

TL;DR

This paper demonstrates high-fidelity imaging of $^{171}$Yb atoms in shallow clock-magic tweezers using dual-tone narrowline cooling, enabling efficient, nondestructive qubit measurements and paving the way for large-scale quantum systems.

Contribution

The authors introduce an alternating dual-tone narrowline cooling method for efficient imaging in shallow traps, achieving near 99.9% fidelity without repumping.

Findings

Imaging fidelity exceeds 99.9% in shallow 200 μK traps.

The method allows several-millisecond imaging without significant atom loss.

Simulations suggest further trap depth reduction is possible for improved performance.

Abstract

We demonstrate imaging $^{171}$Yb single atoms in clock-magic tweezers of 759.4 nm wavelength, with above 99.9% fidelity and survival. We use alternating dual-tone narrowline imaging for more efficient three-dimensional cooling in tweezers, allowing several-millisecond imaging in 200 $\mu$K trap depth, which is half of typical depth used for imaging in clock-magic tweezers. Accordingly, even without repumping, imaging survival is still close to 99.9% with the high fidelity, which can enable high performance nondestructive qubit measurements based on metastable shelving. Moreover, our simulation predicts that more optimal configuration could further reduce the trap depth, as improving the imaging performance. This imaging capability in shallow traps opens high performance imaging for more general trap wavelength, and lays the foundation for large scale systems over 1,000 qubits, and highly repeatable tweezer clocks.