Suppression of clock shifts at field-insensitive transitions

TL;DR

This paper demonstrates how to significantly suppress quadrupole and tensor polarizability shifts in atomic clock transitions by operating at specific field-insensitive points, enhancing multi-ion clock feasibility.

Contribution

It introduces a method to reduce clock transition shifts at field-insensitive points, enabling near-elimination of shifts and improving multi-ion clock operation.

Findings

Shifts can be nearly eliminated at specific field-insensitive points.

The method enhances the feasibility of large ion crystal clocks.

Different geometric constraints affect clock operation modes.

Abstract

We show that it is possible to significantly reduce quadrupole and tensor polarizability shifts of a clock transition by operating at a judiciously chosen field-insensitive point. In some cases shifts are almost completely eliminated making the transition an effective J = 0 to J = 0 candidate. This significantly improves the feasibility of a recent proposal for clock operation with large ion crystals. For such multi-ion clocks, geometric constraints and selection rules naturally divide clock operation into two categories based on the orientation of the magnetic field. We discuss the limitations imposed on each type and how calibrations might be carried out for clock operation.