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Title: Direct Measurement of Quantum Phase Gradients in Superfluid {sup 4}He Flow

Abstract

We report a new kind of experiment in which we generate a known superfluid velocity in a straight tube and directly determine the phase difference across the tube's ends using a superfluid matter wave interferometer. By so doing, we quantitatively verify the relation between the superfluid velocity and the phase gradient of the condensate macroscopic wave function. Within the systematic error of the measurement ({approx}10%) we find {nu}{sub s}=({Dirac_h}/2{pi})/m{sub 4}{nabla}{phi}.

Authors:
; ;  [1]
  1. Physics Department, University of California, Berkeley, California 94720 (United States)
Publication Date:
OSTI Identifier:
20951355
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 19; Other Information: DOI: 10.1103/PhysRevLett.98.195302; (c) 2007 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; ERRORS; HELIUM 4; INTERFEROMETERS; SUPERFLUIDITY; VELOCITY; WAVE FUNCTIONS

Citation Formats

Sato, Yuki, Joshi, Aditya, and Packard, Richard. Direct Measurement of Quantum Phase Gradients in Superfluid {sup 4}He Flow. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.195302.
Sato, Yuki, Joshi, Aditya, & Packard, Richard. Direct Measurement of Quantum Phase Gradients in Superfluid {sup 4}He Flow. United States. doi:10.1103/PHYSREVLETT.98.195302.
Sato, Yuki, Joshi, Aditya, and Packard, Richard. Fri . "Direct Measurement of Quantum Phase Gradients in Superfluid {sup 4}He Flow". United States. doi:10.1103/PHYSREVLETT.98.195302.
@article{osti_20951355,
title = {Direct Measurement of Quantum Phase Gradients in Superfluid {sup 4}He Flow},
author = {Sato, Yuki and Joshi, Aditya and Packard, Richard},
abstractNote = {We report a new kind of experiment in which we generate a known superfluid velocity in a straight tube and directly determine the phase difference across the tube's ends using a superfluid matter wave interferometer. By so doing, we quantitatively verify the relation between the superfluid velocity and the phase gradient of the condensate macroscopic wave function. Within the systematic error of the measurement ({approx}10%) we find {nu}{sub s}=({Dirac_h}/2{pi})/m{sub 4}{nabla}{phi}.},
doi = {10.1103/PHYSREVLETT.98.195302},
journal = {Physical Review Letters},
number = 19,
volume = 98,
place = {United States},
year = {Fri May 11 00:00:00 EDT 2007},
month = {Fri May 11 00:00:00 EDT 2007}
}
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