Decoherence induced by a fluctuating Aharonov-Casher phase (8 pages)

Markus K onig, Ewelina M. Hankiewicz, Jairo Sinova +7 more

P.M.T. Barboza, K. Bakke

Fernando C. Lombardo, Francisco Diego Mazzitelli, Paula I. Villar

Dipole interference is studied when atomic systems are coupled to classical electromagnetic fields. The interaction between the dipoles and the classical fields induces a time-varying Aharonov-Casher phase. Averaging over the phase generates a suppression of fringe visibility in the interference pattern. We show that, for suitable experimental conditions, the loss of contrast for dipoles can be observable and almost as large as the corresponding one for coherent electrons. We analyze different trajectories in order to show the dependence of the decoherence factor with the velocity of the particles.

Xiao-Gang He

Apostol Vourdas

A unified approach to Aharonov-Bohm, Aharonov-Casher and which-path experiments is presented, using an enlarged Hilbert space. This Hilbert space contains quasi-periodic Aharonov-Bohm wavefunctions R ( x +2 ) = R ( x )exp(i ) with various values of . Thus it can describe which-path Aharonov-Bohm experiments where the phase is uncertain due to decoherence that occurs as a result of the observation of the paths of the electric charges. The same Hilbert space contains quasi-periodic Aharonov-Casher wavefunctions which describe magnetic flux tubes winding around an electric charge and which are related through a Fourier transform to the Aharonov-Bohm wavefunctions. The duality between these two phenomena is discussed. The decoherence occuring in which-path experiments is studied quantitatively. Magnetic and electric superselection rules, appropriate for the Aharonov-Bohm and Aharonov-Casher experiments correspondingly, are also discussed.

Keita Kobayashi, H. AIKAWA, Shingo Katsumoto +1 more