Progress toward a measurement of the electron electrical dipole moment using ultra-cold atoms

Fang Fang

Published Jan 29, 2016• 1 citation

Abstract

In this thesis, the basic principles of the C, P, T symmetries are introduced and the experiments to measure the electric dipole moment (EDM) are summarized. We propose an experiment to search for the electric dipole moment of the electron using Cs and Rb atoms in 1D optical lattice traps. Our projected sensitivity is 3iN10-30 e-cm with an integration time of 12 hours, which is a 500-fold improvement over the current limit. The potential sources of noise and systematic errors in our designed experiment are analyzed. The preliminary test results for charging small ITO coated electric field plates are given, and the designs of a magnetic shielding system and cancellation coils are also described. We trapped the Cs and Rb atoms in the MOT, and launched Cs atoms up 90 cm from the MOT to the center of the measurement chamber while guided by a resonator enhanced 1D optical lattice trap with transport efficiency up to 50%. The 1064 nm wavelength optical lattice is made in a 2 m long build-up cavity of light, and provides a transverse guide depth of up to 250 ƒÝK. Before they reach the top of their trajectory, the atoms are stopped and cooled by optical molasses, becoming trapped in the 1D lattice. We also demonstrate multiple launches of Cs atoms to the trap.

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