A low maintenance Sr optical lattice clock

TL;DR

This paper presents a highly reliable Sr optical lattice clock with innovative stabilization techniques, achieving long operational uptime and exceptional stability, advancing the development of optical time-scales.

Contribution

Introduction of a low-maintenance Sr optical lattice clock with enhanced reliability and minimal human intervention for continuous operation.

Findings

84% uptime over 25 days

Instability of 2×10⁻¹⁷ after 10⁵ seconds

Over 500 hours of continuous data collection

Abstract

We describe the Sr optical lattice clock apparatus at NPL with particular emphasis on techniques used to increase reliability and minimise the human requirement in its operation. Central to this is a clock-referenced transfer cavity scheme for the stabilisation of cooling and trapping lasers. We highlight several measures to increase the reliability of the clock with a view towards the realisation of an optical time-scale. The clock contributed 502 hours of data over a 25 day period (84% uptime) in a recent measurement campaign with several uninterrupted periods of more than 48 hours. An instability of $2\times10^{-17}$ was reached after $10^5$ s of averaging in an interleaved self-comparison of the clock.