A Rubidium Frequency-standard Based on a MEMS Vapour Cell

An optical atomic frequency-reference based on a vapour of atoms is a strong candidate for a creating a portable atomic clock with sufficient stability to be a reliable independent timing system for major infrastructure in the event of GNSS denial. We present the development of optical atomic frequency-standards within the University of Strathclyde, where MEMS vapour cells and lasers have been developed for a miniaturised rubidium frequency-reference. Existing chip-scale systems have been demonstrated by others using a microwave transition, however an optical clock offers a significantly higher frequency to enable a lower instability.