Magnetic trapping of ultracold Rydberg atoms in low angular momentum states

TL;DR

This paper explores the quantum trapping of ultracold Rydberg atoms in magnetic fields, highlighting how their two-body nature affects trapping and the implications for quantum information processing.

Contribution

It provides analytical models for Rydberg atom trapping potentials and examines the impact of Rydberg excitation on atom dynamics and qubit purity.

Findings

Two-body effects significantly alter trapping properties.

Analytical expressions accurately describe trapping potentials.

Rydberg excitation induces heating affecting qubit coherence.

Abstract

We theoretically investigate the quantum properties of nS, nP, and nD Rydberg atoms in a magnetic Ioffe-Pritchard trap. In particular, it is demonstrated that the two-body character of Rydberg atoms significantly alters the trapping properties opposed to point-like particles with identical magnetic moment. Approximate analytical expressions describing the resulting Rydberg trapping potentials are derived and their validity is confirmed for experimentally relevant field strengths by comparisons to numerical solutions of the underlying Schroedinger equation. In addition to the electronic properties, the center of mass dynamics of trapped Rydberg atoms is studied. In particular, we analyze the influence of a short-time Rydberg excitation, as required by certain quantum-information protocols, on the center of mass dynamics of trapped ground state atoms. A corresponding heating rate is derived and the implications for the purity of the density matrix of an encoded qubit are investigated.