Lucas GROULT : "Conception of microfabricated Paul trap for a Yb+ trapped ion based, compact optical clock"

Abstract : Thanks to Hans Dehmelt’s works, the field of frequencies and time measurement has immensely improved since the seventies. The emergence, in the early twentieth century, of the firsts atomic clocks, then of optical frequencies combs enabled the dawn of optical clocks. This kind of dispositive represents a major interest in in numerous disciplines of physics for it allows to dispense a signal that’s simultaneously stable and accurate at unreachable levels via mechanical or piezoelectrical means.

Besides the numerous uses for the clocks, especially in telecommunications activities area, satellite navigation and aerospace, such performances lead the way to other possibilities, as in geodesy or in fundamental physics. Among many fields where compact clocks can be used, lots of them are interested in their compactness and their transportability. Embedded systems in the first place are always most regarding, towards volume, efficiency and energy consumption. Other applications, like geodesy, require to convey and use the equipment in the field.

In this context began the development of the ion Yb+ compact optical clock at the FEMTO-ST Institute in 2014. The purpose is to process an atomic clock which total volume below 500L and able to reach performances above those of a hydrogen MASER by a factor ten. My work began in 2016, by setting up the complete experimental system, from the optical benches, to the laser sources used to create, cool and handle ions, to vacuum the experimental chamber and capture the first ions. The current trap is a prototypical surface trap, conceived to activate quickly the experimental system and achieve the first trapping of ions. As such, it suffers various defaults and my work subsequently went to design and produce a new trap, using the clean room’s resources (MIMENTO technology central) by micro-manufacturing with micro electromechanical systems techniques.

Jury Composition  : 

Luca Guidoni, Université Paris-Diderot, Paris 7, Reporter

Martina Knoop, Université Aix-Marseille, Reporter

Vincent Giordano, Université Bourgogne Franche-comté, Reviewer

Clément Lacroûte, Université Bourgogne Franche-comté, Reviewer

Yann Kersalé, Université Bourgogne Franche-comté, PhD Director

Romain Long, Sorbonne Université (ENS), Reviewer

Thomas lévèque, CNES, Reviewer

Localization : Amphithéâtre Jules Haag - ENSMM - 26, Rue de l'Epitaphe - Besançon