You need JavaScript to view this

Atom interferometry experiments with lithium. Accurate measurement of the electric polarizability; Experiences d'interferometrie atomique avec le lithium. Mesure de precision de la polarisabilite electrique

Abstract

Atom interferometers are very sensitive tools to make precise measurements of physical quantities. This study presents a measurement of the static electric polarizability of lithium by atom interferometry. Our result, {alpha} = (24.33 {+-} 0.16)*10{sup -30} m{sup 3}, improves by a factor 3 the most accurate measurements of this quantity. This work describes the tuning and the operation of a Mach-Zehnder atom interferometer in detail. The two interfering arms are separated by the elastic diffraction of the atomic wave by a laser standing wave, almost resonant with the first resonance transition of lithium atom. A set of experimental techniques, often complicated to implement, is necessary to build the experimental set-up. After a detailed study of the atom source (a supersonic beam of lithium seeded in argon), we present our experimental atom signals which exhibit a very high fringe visibility, up to 84.5 % for first order diffraction. A wide variety of signals has been observed by diffraction of the bosonic isotope at higher diffraction orders and by diffraction of the fermionic less abundant isotope. The quality of these signals is then used to do very accurate phase measurements. A first experiment investigates how the atom interferometer signals are modified by  More>>
Authors:
Publication Date:
Jun 15, 2005
Product Type:
Thesis/Dissertation
Report Number:
FRNC-TH-6498
Resource Relation:
Other Information: TH: These physique quantique; 251 refs
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; HYPERFINE STRUCTURE; LITHIUM 6; LITHIUM 7; MACH-ZEHNDER INTERFEROMETER; POLARIZABILITY; TUNING; ZEEMAN EFFECT
OSTI ID:
20754753
Research Organizations:
Universite Paul Sabatier, 31 - Toulouse (France)
Country of Origin:
France
Language:
French
Other Identifying Numbers:
TRN: FR0601259062550
Availability:
Available from INIS in electronic form
Submitting Site:
FRN
Size:
258 pages
Announcement Date:
Aug 14, 2006

Citation Formats

Miffre, A. Atom interferometry experiments with lithium. Accurate measurement of the electric polarizability; Experiences d'interferometrie atomique avec le lithium. Mesure de precision de la polarisabilite electrique. France: N. p., 2005. Web.
Miffre, A. Atom interferometry experiments with lithium. Accurate measurement of the electric polarizability; Experiences d'interferometrie atomique avec le lithium. Mesure de precision de la polarisabilite electrique. France.
Miffre, A. 2005. "Atom interferometry experiments with lithium. Accurate measurement of the electric polarizability; Experiences d'interferometrie atomique avec le lithium. Mesure de precision de la polarisabilite electrique." France.
@misc{etde_20754753,
title = {Atom interferometry experiments with lithium. Accurate measurement of the electric polarizability; Experiences d'interferometrie atomique avec le lithium. Mesure de precision de la polarisabilite electrique}
author = {Miffre, A}
abstractNote = {Atom interferometers are very sensitive tools to make precise measurements of physical quantities. This study presents a measurement of the static electric polarizability of lithium by atom interferometry. Our result, {alpha} = (24.33 {+-} 0.16)*10{sup -30} m{sup 3}, improves by a factor 3 the most accurate measurements of this quantity. This work describes the tuning and the operation of a Mach-Zehnder atom interferometer in detail. The two interfering arms are separated by the elastic diffraction of the atomic wave by a laser standing wave, almost resonant with the first resonance transition of lithium atom. A set of experimental techniques, often complicated to implement, is necessary to build the experimental set-up. After a detailed study of the atom source (a supersonic beam of lithium seeded in argon), we present our experimental atom signals which exhibit a very high fringe visibility, up to 84.5 % for first order diffraction. A wide variety of signals has been observed by diffraction of the bosonic isotope at higher diffraction orders and by diffraction of the fermionic less abundant isotope. The quality of these signals is then used to do very accurate phase measurements. A first experiment investigates how the atom interferometer signals are modified by a magnetic field gradient. An absolute measurement of lithium atom electric polarizability is then achieved by applying a static electric field on one of the two interfering arms, separated by only 90 micrometers. The construction of such a capacitor, its alignment in the experimental set-up and its operation are fully detailed.We obtain a very accurate phase measurement of the induced Lo Surdo - Stark phase shift (0.07 % precision). For this first measurement, the final uncertainty on the electric polarizability of lithium is only 0.66 %, and is dominated by the uncertainty on the atom beam mean velocity, so that a further reduction of the uncertainty can be expected. (author)}
place = {France}
year = {2005}
month = {Jun}
}