Unprecedented High Long Term Frequency Stability with a Macroscopic Resonator Oscillator

TL;DR

This paper presents a cryogenic sapphire oscillator with a novel design achieving record-breaking long-term frequency stability of better than 4.5e-15 over a day, surpassing previous macroscopic resonator sources.

Contribution

The paper introduces a new cryogenic sapphire oscillator design using an autonomous pulse-tube cryocooler, achieving unprecedented long-term frequency stability.

Findings

Achieved relative frequency stability better than 4.5e-15 over one day

Set a new record for long-term stability with macroscopic resonator-based sources

Demonstrated the effectiveness of the cryocooler design in stability performance

Abstract

This article reports on the long-term frequency stabilty characterisation of a new type of cryogenic sapphire oscillator using an autonomous pulse-tube cryocooler as its cold source. This new design enables a relative frequency stability of better than 4.5e-15 over one day of integration. This represents to our knowledge the best long-term frequency stability ever obtained with a signal source based on a macroscopic resonator.