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arXiv:2610.35588

A low-volume cold-atom microwave clock with an additively manufactured cavity

Samuel A. Smith, Sean Dyer, Alan Bregazzi, Rajnandan Choudhury Das, Oliver S. Burrow, C. Affolderbach, G. Mileti, Erling Riis, Paul F. Griffin

Published Oct 26, 2026• 0 citations
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Abstract

We present the performance of a compact microwave interrogated atomic clock based on laser cooled $^{87}$$\rm{Rb}$ atoms. The clock utilizes a micro-fabricated grating magneto-optical trap (gMOT) to cool and trap atoms, and an additively manufactured microwave cavity for microwave interrogation. We demonstrate a signal-to-noise ratio (SNR) of $370$ at a 1 Hz bandwidth and mid-term instability of $6.7\times10^{-14}$ at an averaging time of $τ=3 \times 10^{4}$ s. In addition, a low cost mu-metal foil has been implemented on the vacuum chamber to reduce the quadratic Zeeman shift which was previously limiting stability beyond $τ= 10$ s.

DOI
10.48550/arxiv.2610.35588

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