High accuracy measure of atomic polarizability in an optical lattice clock

TL;DR

This paper precisely measures the atomic polarizability in an ytterbium optical clock, significantly reducing the uncertainty caused by blackbody radiation and enhancing clock accuracy.

Contribution

It provides the most accurate determination of the differential static polarizability in an optical clock, improving blackbody radiation uncertainty estimates.

Findings

Differential static polarizability: 36.2612(7) kHz (kV/cm)^{-2}

Blackbody radiation uncertainty reduced to 3×10^{-17}

Enhanced precision in Stark effect characterization

Abstract

Despite being a canonical example of quantum mechanical perturbation theory, as well as one of the earliest observed spectroscopic shifts, the Stark effect contributes the largest source of uncertainty in a modern optical atomic clock through blackbody radiation. By employing an ultracold, trapped atomic ensemble and high stability optical clock, we characterize the quadratic Stark effect with unprecedented precision. We report the ytterbium optical clock's sensitivity to electric fields (such as blackbody radiation) as the differential static polarizability of the ground and excited clock levels: 36.2612(7) kHz (kV/cm)^{-2}. The clock's fractional uncertainty due to room temperature blackbody radiation is reduced an order of magnitude to 3 \times 10^{-17}.