# Enhancing Kondo Coupling in Alkaline-Earth Atomic Gases with Confinement-induced Resonances in Mixed Dimensions

## TL;DR

This paper proposes a method to enhance the Kondo coupling in ultracold alkaline-earth atomic gases by using combined transverse and axial confinement-induced resonances, potentially enabling experimental observation of the Kondo effect.

## Contribution

It introduces a novel approach of using axial harmonic confinement along with transverse confinement to reach confinement-induced resonance in mixed-dimensional systems, improving Kondo coupling control.

## Key findings

- Axial confinement acts as an additional control for resonance.
- Combined confinements enable reaching the resonance under practical conditions.
- Enhanced Kondo effect is feasible in ultracold atomic gases with this method.

## Abstract

The Kondo effect describes the spin-exchanging interaction between localized impurity and the itinerant fermions. The ultracold alkaline-earth atomic gas provides a natural platform for quantum simulation of the Kondo model, utilizing its long-lived clock state and the nuclear-spin exchanging interaction between the clock state and the ground state. One of the key issue now is whether the Kondo temperature can be high enough to be reached in current experiment, for which we have proposed using a transverse confinement to confine atoms into a one-dimensional tube and to utilize the confinement-induced resonance to enhance the Kondo coupling. In this work, we further consider the $1+0$ dimensional scattering problem when the clock state is further confined by an axial harmonic confinement. We show that this axial confinement for the clock state atoms not only plays a role for localizing them, but also can act as an additional control knob to reach the confinement-induced resonance. We show that by combining both the transverse and the axial confinements, the confinement-induced resonance can be reached in the practical conditions and the Kondo effect can be attainable in this system.