Engineering the Kondo impurity problem with alkaline-earth atom arrays

TL;DR

This paper proposes using cold alkaline-earth atom arrays to simulate the Kondo impurity problem, analyzing how to observe and control the Kondo effect in realistic experimental setups.

Contribution

It introduces a detailed ab initio model for simulating the Kondo effect with alkaline-earth atoms and identifies methods to restore the Kondo effect by local chemical potential adjustments.

Findings

Identification of additional terms affecting Kondo physics in cold-atom systems

Demonstration that local chemical potential tuning can restore the Kondo effect

Proposal of experimental protocols for observing Kondo signatures in alkaline-earth atom arrays

Abstract

We propose quantum simulation experiments of the Kondo impurity problem using cold alkaline-earth(-like) atoms (AEAs) in a combination of optical lattice and optical tweezer potentials. Within an ab initio model for atomic interactions in the optical potentials, we analyze hallmark signatures of the Kondo effect in a variety of observables accessible in cold-atom quantum simulators. We identify additional terms not part of the textbook Kondo problem, mostly ignored in previous works and giving rise to a direct competition between spin and charge correlations - strongly suppressing Kondo physics. We show that the Kondo effect can be restored by locally adjusting the chemical potential on the impurity site, and we identify realistic parameter regimes and preparation protocols suited to current experiments with AEA arrays. Our work paves the way for novel quantum simulations of the Kondo problem and offers new insights into Kondo physics in unconventional regimes.