First observation and measurement of the ${}^{198}\text{Hg}$ bosonic transition in an optical lattice clock

TL;DR

This paper reports the first observation of a specific magnetic-field-induced transition in the 198Hg bosonic isotope within an optical lattice clock, including its characterization and comparison with 87Sr, achieving high stability and precise frequency ratio measurement.

Contribution

First observation and detailed characterization of the 198Hg bosonic transition in an optical lattice clock, including a direct frequency ratio measurement with 87Sr.

Findings

198Hg optical lattice clock stability of 6x10^-16/√t

Total systematic uncertainty of 6.9x10^-16

First direct measurement of 198Hg/87Sr frequency ratio

Abstract

We report the first observation of the magnetic-field-induced (5d10 6s2)1S0-(5d10 6s6p)3P0 transition in a bosonic isotope of mercury, 198Hg, realized in an optical lattice clock. We characterize this new isotope, determining key features such as the quadratic Zeeman shift, the probe light shift, and the magic frequency. We also report a first comparison between the 198Hg optical lattice clock and 87Sr. In this comparison, the 198Hg clock has a relative frequency stability of 6x10-16/sqrt(tau/s) and a total relative systematic uncertainty of 6.9x10-16. This comparison yields the first direct determination of the 198Hg/87Sr optical frequency ratio: 198Hg/87Sr = 2.629 315 734 684 118 1, with the same relative uncertainty.