Trapped arrays of alkaline earth Rydberg atoms in optical tweezers

TL;DR

This paper demonstrates stable trapping of alkaline earth Rydberg atoms in optical tweezers, achieving long lifetimes and coherence times, which enhances their potential for quantum simulation and computing.

Contribution

It introduces a method to trap Rydberg states of ytterbium atoms using the same optical tweezer as ground states, enabling longer coherence and interaction times.

Findings

Rydberg states of ytterbium can be stably trapped with lifetimes over 100 microseconds.

No auto- or photo-ionization observed from trap light for these states.

Coherence time between Rydberg levels exceeds 59 microseconds.

Abstract

Neutral atom qubits with Rydberg-mediated interactions are a leading platform for developing large-scale coherent quantum systems. In the majority of experiments to date, the Rydberg states are not trapped by the same potential that confines ground state atoms, resulting in atom loss and constraints on the achievable interaction time. In this work, we demonstrate that the Rydberg states of an alkaline earth atom, ytterbium, can be stably trapped by the same red-detuned optical tweezer that also confines the ground state, by leveraging the polarizability of the Yb$^+$ ion core. Using the previously unobserved \tripletS series, we demonstrate trapped Rydberg atom lifetimes exceeding $100\,\mu$s, and observe no evidence of auto- or photo-ionization from the trap light for these states. We measure a coherence time of $T_2 = 59$ $\mu$s between two Rydberg levels, exceeding the 28 $\mu$s lifetime of untrapped Rydberg atoms under the same conditions. These results are promising for extending the interaction time of Rydberg atom arrays for quantum simulation and computing, and are vital to capitalize on the extended Rydberg lifetimes in circular states or cryogenic environments.