Skip to Main content Skip to Navigation
Theses

Interféromètres atomiques piégés : du régime dilué au régime dense

Abstract : This thesis presents the recent progress on the FORCA-G (FORce de CAsimir et Gravitation à courte distance) experiment which aims at measuring short range forces between an atom, trapped in a vertical optical lattice, and a mirror. Stimulated Raman transitions are used to induce coherent transport between adjacent lattice sites to perform atom interferometry in order to measure with very high sensitivity, shifts in the Bloch frequency \nu_B, which is the potential increment between two lattice sites. For low atomic densities, we demonstrate a local force sensor with state-of-the art relative sensitivity on the Bloch frequency of \delta\nu_B/ \nu_B = 1.8x10-6 at 1 s. The recent use of evaporative cooling, in order to increase the number of atoms per well, allows to work the experiment with much denser atomic clouds where atom interactions cannot be neglected. At densities of 10^11-10^12 at/cm3, it is shown that a spin self-rephasing mechanism competes with the spin-echo technique. The impact of the former mechanism onto the contrast and the measured frequency is studied in an interferometer where the two partial wave packets perfectly overlap. First measurements are then performed in a regime where the two partial wave packets are spatially separated. They show a different behaviour that remains to be modelled. Finally, it is shown that the measurement protocol allows to greatly reduce collisional shifts: atom interactions limit the sensitivity of the local force sensor without limiting its accuracy.
Complete list of metadatas

Cited literature [212 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-01462275
Contributor : Cyrille Solaro <>
Submitted on : Wednesday, February 8, 2017 - 6:05:04 PM
Last modification on : Thursday, April 2, 2020 - 1:28:57 PM
Document(s) archivé(s) le : Tuesday, May 9, 2017 - 1:46:26 PM

Identifiers

  • HAL Id : tel-01462275, version 1

Citation

Cyrille Solaro. Interféromètres atomiques piégés : du régime dilué au régime dense. Physique [physics]. Université Pierre et Marie Curie, 2016. Français. ⟨tel-01462275⟩

Share

Metrics

Record views

272

Files downloads

147