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Title: Noise Thermometry with Two Weakly Coupled Bose-Einstein Condensates

Abstract

Here we report on the experimental investigation of thermally induced fluctuations of the relative phase between two Bose-Einstein condensates which are coupled via tunneling. The experimental control over the coupling strength and the temperature of the thermal background allows for the quantitative analysis of the phase fluctuations. Furthermore, we demonstrate the application of these measurements for thermometry in a regime where standard methods fail. With this we confirm that the heat capacity of an ideal Bose gas deviates from that of a classical gas as predicted by the third law of thermodynamics.

Authors:
; ; ; ;  [1]
  1. Kirchhoff-Institut fuer Physik, Universitaet Heidelberg, Im Neuenheimer Feld 227, D-69120 Heidelberg (Germany)
Publication Date:
OSTI Identifier:
20775150
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 13; Other Information: DOI: 10.1103/PhysRevLett.96.130404; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BOSE-EINSTEIN CONDENSATION; BOSE-EINSTEIN GAS; FLUCTUATIONS; NOISE THERMOMETERS; SPECIFIC HEAT; THERMODYNAMICS; TUNNEL EFFECT

Citation Formats

Gati, Rudolf, Hemmerling, Boerge, Foelling, Jonas, Albiez, Michael, and Oberthaler, Markus K. Noise Thermometry with Two Weakly Coupled Bose-Einstein Condensates. United States: N. p., 2006. Web. doi:10.1103/PhysRevLett.96.130404.
Gati, Rudolf, Hemmerling, Boerge, Foelling, Jonas, Albiez, Michael, & Oberthaler, Markus K. Noise Thermometry with Two Weakly Coupled Bose-Einstein Condensates. United States. doi:10.1103/PhysRevLett.96.130404.
Gati, Rudolf, Hemmerling, Boerge, Foelling, Jonas, Albiez, Michael, and Oberthaler, Markus K. Fri . "Noise Thermometry with Two Weakly Coupled Bose-Einstein Condensates". United States. doi:10.1103/PhysRevLett.96.130404.
@article{osti_20775150,
title = {Noise Thermometry with Two Weakly Coupled Bose-Einstein Condensates},
author = {Gati, Rudolf and Hemmerling, Boerge and Foelling, Jonas and Albiez, Michael and Oberthaler, Markus K.},
abstractNote = {Here we report on the experimental investigation of thermally induced fluctuations of the relative phase between two Bose-Einstein condensates which are coupled via tunneling. The experimental control over the coupling strength and the temperature of the thermal background allows for the quantitative analysis of the phase fluctuations. Furthermore, we demonstrate the application of these measurements for thermometry in a regime where standard methods fail. With this we confirm that the heat capacity of an ideal Bose gas deviates from that of a classical gas as predicted by the third law of thermodynamics.},
doi = {10.1103/PhysRevLett.96.130404},
journal = {Physical Review Letters},
number = 13,
volume = 96,
place = {United States},
year = {Fri Apr 07 00:00:00 EDT 2006},
month = {Fri Apr 07 00:00:00 EDT 2006}
}
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