Evaluation of lattice light shift at low 10$^{-19}$ uncertainty for a shallow lattice Sr optical clock

TL;DR

This paper reports a precise evaluation of lattice light shift in a Wannier-Stark optical lattice clock, achieving a fractional frequency uncertainty of 3.5×10⁻¹⁹, advancing the clock's accuracy.

Contribution

It provides a systematic measurement of lattice light shift contributions at unprecedented precision, crucial for improving optical clock accuracy.

Findings

Measured multipolar and hyperpolar contributions to lattice light shift.

Achieved fractional frequency uncertainty of 3.5×10⁻¹⁹.

Demonstrated control of atomic motional states in the lattice.

Abstract

A Wannier-Stark optical lattice clock has demonstrated unprecedented measurement precision for optical atomic clocks. We present a systematic evaluation of the lattice light shift, a necessary next step for establishing this system as an accurate atomic clock. With precise control of the atomic motional states in the lattice, we report accurate measurements of the multipolar and the hyperpolar contributions and the operational lattice light shift with a fractional frequency uncertainty of 3.5$\times$10${}^{-19}$.