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Measurement Induced Dephasing and Suppression of Persistent Current in a Lattice Ring

Yong-Ping Zhang·Ying-Fang Gao·J. -Q. Liang
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Abstract

We investigate the effect of measurement on the persistent current density in a lattice ring penetrated by an Aharonov-Bohm flux and coupled to a quantum dot which is continuously monitored by a point contact detector. It is demonstrated by explicit analysis of the time-evolution of current density that the persistent current in the lattice ring is suppressed completely due to dephasing of quantum states induced by an analogous which-way-measurment that whether or not the electron is localized on the quantum dot. Practical experiments to observe the measurment induced dephasing is proposed.

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Yong-Ping Zhang, Ying-Fang Gao, J. -Q. Liang. 2005-11-08. Measurement Induced Dephasing and Suppression of Persistent Current in a Lattice Ring. https://doi.org/10.1016/j.physleta.2005.07.050

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