Measuring atomic properties with an atom interferometer

Two experiments are presented which measure atomic properties using an atom interferometer. The interferometer splits the sodium de Broglie wave into two paths, one of which travels through an interaction region. The paths are recombined, and the interference pattern exhibits a phase shift depending on the strength of the interaction. In the first experiment, the interaction involves a gas. De Broglie waves traveling through the gas experience a phase shift represented by an index of refraction. By measuring the index of refraction at various wavelengths, the predicted phenomenon of glory oscillations in the phase shift has been observed for the first time. The index of refraction has been measured for sodium atoms in gases of argon, krypton, xenon, and nitrogen over a wide range of wavelength. These measurements offer detailed insight into the interatomic potential between sodium atoms and the gases. Theoretical predictions of the interatomic potentials are challenged by these results, which should encourage a renewed effort to better understand these potentials. The second experiment measures atomic polarizability with an atom interferometer. Here, the interaction is with an electric field; the atom experiences a phase shift proportional to its energy inside the field. Previously, this method was used to perform the most accurate (< 1%) measurement of sodium polarizability. The precision was limited, however, by the spread of velocities in the atomic beam-the phase shift is different depending on velocity, and the -interference pattern is washed out.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Physics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2002

Author dc:creator

• Roberts, Tony David, 1972-

Advisor dc:contributor.advisor

• David E. Pritchard.

• Physics.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/29302

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/29302