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Interferometric measurement of the resonant absorption and refractive index in rubidium gas

Libbrecht, K. G. and Libbrecht, M. W. (2006) Interferometric measurement of the resonant absorption and refractive index in rubidium gas. American Journal of Physics, 74 (12). pp. 1055-1060. ISSN 0002-9505. doi:10.1119/1.2335476.

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We present a laboratory demonstration of the Kramers-Kronig relation between the resonant absorption and refractive index in rubidium gas. Our experiment uses a rubidium vapor cell in one arm of a simple Mach-Zehnder interferometer. As the laser frequency is scanned over an atomic resonance, the interferometer output is affected by variations of both the absorption and refractive index of the gas with frequency, all of which can be calculated in a straightforward manner. Changing the vapor density and interferometer phase produces a family of different output signals. The experiment was performed using a commercially available tunable diode laser system that was designed specifically for the undergraduate physics laboratory. As a teaching tool this experiment is reliable, fun, and instructive, while it also introduces the student to some sophisticated and fundamental physical concepts.

Item Type:Article
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Libbrecht, K. G.0000-0002-8744-3298
Additional Information:© 2008 American Association of Physics Teachers. Received 17 April 2006; accepted 14 July 2006. This material is based upon work supported by the National Science Foundation under Grant No. 0340559.
Funding AgencyGrant Number
National Science Foundation0340559
Subject Keywords:student experiments, resonant states, refractive index, Kramers-Kronig relations, Mach-Zehnder interferometers, rubidium
Issue or Number:12
Record Number:CaltechAUTHORS:LIBajp06
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:12639
Deposited By: Tony Diaz
Deposited On:30 Jan 2009 00:48
Last Modified:08 Nov 2021 22:31

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