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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 15, Iss. 19 — Sep. 17, 2007
  • pp: 12114–12122

Direct Measurement of the Atom Number in a Bose Condensate

Hung-Wen Cho, Yan-Cheng He, Thorsten Peters, Yi-Hsin Chen, Han-Chang Chen, Sheng-Chiun Lin, Yi-Chi Lee, and Ite A. Yu  »View Author Affiliations

Optics Express, Vol. 15, Issue 19, pp. 12114-12122 (2007)

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We report on directly measuring the atom number in a Bose-Einstein condensate by the method of optical pumping. Only the branching ratio of the spontaneous decay in the system and the absorption energy of a probe laser beam are required to determine the atom number. The measured absorption energy is not affected by the measurement condition such as the intensity, detuning, and polarization of the probe beam, the magnetic field, etc. We have shown that atom numbers as low as a few thousands can be measured. The atom number is an important parameter in the studies of Bose condensates and its accuracy is greatly improved by this sensitive and robust method.

© 2007 Optical Society of America

OCIS Codes
(120.1880) Instrumentation, measurement, and metrology : Detection
(300.1030) Spectroscopy : Absorption
(020.3320) Atomic and molecular physics : Laser cooling

ToC Category:
Atomic and Molecular Physics

Original Manuscript: June 28, 2007
Revised Manuscript: September 6, 2007
Manuscript Accepted: September 6, 2007
Published: September 7, 2007

Hung-Wen Cho, Yan-Cheng He, Thorsten Peters, Yi-Hsin Chen, Han-Chang Chen, Sheng-Chiun Lin, Yi-Chi Lee, and Ite A. Yu, "Direct measurement of the Atom number in a Bose condensate," Opt. Express 15, 12114-12122 (2007)

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