Light pulse Talbot-Lau interferometry with magnetically guided atoms
By: by Saijun Wu
Series: Collections of the Harvard University Archives
Published: 2007
Language: eng
Number of pages: 370
Description: This thesis discusses the development of an interferometry experiment with magnetically guided atoms using optical standing wave pulses. Ground-state rubidium atoms are confined in a two-dimensional magnetic quadruple field as a guiding potential. An optical standing wave field is pulsed to transfer photon recoil momentum to atoms. We use several Talbot-Lau type interferometry schemes to study the coherence properties of guided atoms, in particular, we identify an interferometry regime where matter-wave dephasing due to the confined motion are suppressed, allowing long coherence time and high precision measurements. This thesis summarizes the design, construction and operation of the experimental apparatus. We discuss the realization of a guided atom accelerometer, precise recoil frequency measurements with guided atoms, an area-enclosing interferometer based on a moving guide for rotation sensing, and a new interferometry configuration to realize a spatial-displacement echo with up to 1s coherence time and with frozen transverse-confinement induced dephasing.

The matter-wave dephasing due to variations of the guiding potential along the nearly-free direction of propagation is identified as the limiting factor on the achievable interferometry precision, which is likely due to the poling inhomogeneities of the ferro-magnetic foils that generate the guiding potential. Two future options using either a precisely-fabricated atom chip or an optical dipole trap are suggested to overcome the difficulty. As the theoretical part of this thesis, a vector theory of the generalized Talbot-Lau type interferometry is discussed using Weyl functions.
Notes: "May 2007."

Thesis (Ph.D., Dept. of Applied Physics)--Harvard University, 2007.

Includes bibliographical references.