Ultracold rare-earth magnetic atoms with an electric dipole moment

TL;DR

This paper introduces a method to create ultracold dysprosium atoms with both electric and magnetic dipole moments by mixing nearly degenerate energy levels using an external electric field, enabling new quantum gas experiments.

Contribution

It proposes a novel technique to induce electric and magnetic dipole moments in ultracold dysprosium atoms through level mixing with an external electric field.

Findings

Electric dipole moment up to 0.22 Debye predicted

Magnetic dipole moment up to 13 Bohr magnetons predicted

Level lifetime in the millisecond range suitable for experiments

Abstract

We propose a new method to produce an electric and magnetic dipolar gas of ultracold dysprosium atoms. The pair of nearly degenerate energy levels of opposite parity, at 17513.33 cm$^{-1}$ with electronic angular momentum $J=10$, and at 17514.50 cm$^{-1}$ with $J=9$, can be mixed with an external electric field, thus inducing an electric dipole moment in the laboratory frame. For field amplitudes relevant to current-day experiments, we predict a magnetic dipole moment up to 13 Bohr magnetons, and an electric dipole moment up to 0.22 Debye, which is similar to the values obtained for alkali-metal diatomics. When a magnetic field is present, we show that the electric dipole moment is strongly dependent on the angle between the fields. The lifetime of the field-mixed levels is found in the millisecond range, thus allowing for suitable experimental detection and manipulation.