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Optics Express

Optics Express

  • Editor: Michael Duncan
  • Vol. 13, Iss. 4 — Feb. 21, 2005
  • pp: 1249–1253

A chip-scale atomic clock based on 87Rb with improved frequency stability

S. Knappe, P.D.D. Schwindt, V. Shah, L. Hollberg, J. Kitching, L. Liew, and J. Moreland  »View Author Affiliations

Optics Express, Vol. 13, Issue 4, pp. 1249-1253 (2005)

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We demonstrate a microfabricated atomic clock physics package based on coherent population trapping (CPT) on the D1 line of 87Rb atoms. The package occupies a volume of 12 mm3 and requires 195 mW of power to operate at an ambient temperature of 200 °C. Compared to a previous microfabricated clock exciting the D2 transition in Cs [1], this 87Rb clock shows significantly improved short- and long-term stability. The instability at short times is 4×10-111/2 and the improvement over the Cs device is due mainly to an increase in resonance amplitude. At longer times (τ>50 s), the improvement results from the reduction of a slow drift to -5×10-9/day. The drift is most likely caused by a chemical reaction of nitrogen and barium inside the cell. When probing the atoms on the D1 line, spin-exchange collisions between Rb atoms and optical pumping appear to have increased importance compared to the D2 line.

© 2005 Optical Society of America

OCIS Codes
(300.6320) Spectroscopy : Spectroscopy, high-resolution
(350.3950) Other areas of optics : Micro-optics

ToC Category:
Research Papers

Original Manuscript: January 11, 2005
Revised Manuscript: January 10, 2005
Published: February 21, 2005

S. Knappe, P. Schwindt, V. Shah, L. Hollberg, J. Kitching, L. Liew, and J. Moreland, "A chip-scale atomic clock based on 87Rb with improved frequency stability," Opt. Express 13, 1249-1253 (2005)

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