Université de Neuchâtel

Rubidium vapour-cell frequency standards : metrology of optical and microwave frequency references

Moreno, William ; Mileti, Gaetano (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2019.

This thesis concerns the development, study, and optimisation of compact and high-performance frequency references based on rubidium (Rb) vapour cells1. More specially, two Rb vapour-cell frequency references are studied: an optical-frequency reference at 1.5 μm and a double-resonance pulsed optically pumped (POP) atomic clock. The use of vapour cells allows compact frequency...

Université de Neuchâtel

Ramsey spectroscopy in a Rubidium vapor cell and realization of an ultra-stable atomic clock

Gharavipour, Mohammadreza ; Mileti, Gaetano (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2018.

Various application fields in industry, telecommunication, navigation and space demand reliable, compact, high-performance frequency standards with a stability level of −14 at 105s (equivalent to <1ns/day). Thanks to semiconductor technology, optical pumping technique with a laser has opened up new schemes based on laser-microwave double-resonance (DR), such as...

Université de Neuchâtel

Fabrication and characterization of MEMS alkali vapor cells used in chip-scale atomic clocks and other atomic devices

Karlen, Sylvain ; Mileti, Gaetano (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2018.

Atomic clocks are timekeeping devices that can achieve extreme performance in terms of stability and accuracy. Behind this name, hides a variety of different systems which size and complexity can be considerably different depending on their applications. The primary frequency standards used for the realization of the second and the clocks mounted on the Galileo satellite positioning system are...

Université de Neuchâtel

High-resolution spectroscopic studies in glass-blown and micro-fabricated cells for miniature rubidium atomic clocks

Pellaton, Matthieu ; Mileti, Gaetano (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2014.

Buffer-gas alkali vapour cells form the heart of essentially all types of commercial compact or miniaturized atomic clocks. They reliably hold and confine a vapour of alkali atoms, which provides the atomic transition frequency serving as stable reference for the clock oscillator. The desire to bring atomic clock stability to portable applications such as telecommunication and navigation...

Université de Neuchâtel

Light-shift and temperature-shift studies in atomic clocks based on coherent population trapping

Miletic, Danijela ; Mileti, Gaetano (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2013.

Vapor-cell atomic clocks exploit the ground-state microwave transition in an alkali atom to provide a stable frequency reference. At the heart of a conventional vapor-cell atomic clock is a cell containing the alkali atoms. A vapor-cell atomic clock can be realized using two different basic principles: Double Resonance (DR) and Coherent Population Trapping (CPT). In DR, the alkali atoms are...

Université de Neuchâtel

Double-resonance studies on compact, high-performance rubidium cell frequency standards

Bandi, Thejesh N ; Mileti, Gaetano (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2013.

This thesis presents experimental studies on continuous-wave (CW) laser-microwave double-resonance (DR) spectroscopy and metrology in rubidium (87Rb) vapor cells in view of new high-performance, compact Rb-cell atomic clocks. The Rb vapor cell is confined inside a magnetron-type cavity microwave resonator (MWR). The CW DR spectroscopy involves two resonant electromagnetic fields that are operated...

Université de Neuchâtel

Évaluation métrologique de l'étalon primaire de fréquence à atomes froids de césium FOCS-2

Devenoges, Laurent ; Mileti, Gaetano (Dir.) ; Thomann, Pierre (Codir.)

Thèse de doctorat : Université de Neuchâtel, 2012.

Ce travail de recherche s'inscrit dans la continuité des études, menées depuis 20 ans à l'Observatoire Cantonal de Neuchâtel, pour réaliser un étalon primaire de fréquence fonctionnant avec un jet continu d'atomes froids et lents. Ces développements théoriques et expérimentaux ont conduit à la construction de deux horloges à fontaine continue FOCS-1 et FOCS-2. Ce document expose les...