Very Recent Development and Significant Step in Ultra-Stable Quartz Oscillators
Résumé
The recent progress in Quartz thanks to the Doubly rotated quartz resonators with a low amplitude-frequency effect called Low isochronism Defect (LD) cut and most of all the very recent development of a new design for integrating a Stressed compensated (SC) cut in an oscillator with the best stability ever obtained with a quartz oscillator, 2.5x10-14 for the flicker frequency modulation (FFM) floor for a 5 MHz Boitiers à Vieillissement Amélioré (BVA) double oven- controlled oscillator open the door to ultra-high stability oscillators for telecommunications, instrumentation and space applications. In this chapter, we propose to describe the main guidelines that led to the first significant development in the last fifteen years in terms of ultra-stable quartz state-of-the-art oscillators. These oscillators are realized in France and Switzerland. It includes the choice of the resonators, the development of adequate electronics and how to mechanically and thermally stabilized such an ultra-stable oscillator. We also present how to characterize the expected performances. Finally we say some words about the use of these Quartz oscillators for space, telecommunication and metrology applications and how their signal can be distributed in a laboratory without degradation of their noise.