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An Electronic Mach-Zehnder Quantum Eraser

Kicheon Kang
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Abstract

We propose an electronic quantum eraser in which the electrons are injected into a mesoscopic conductor at the quantum Hall regime. The conductor is composed of a two-path interferometer which is an electronic analogue of the optical Mach-Zehnder interferometer, and a quantum point contact detector capacitively coupled to the interferometer. While the interference of the output current at the interferometer is shown to be suppressed by the which-path information, we show that the which-path information is erased by the zero-frequency cross correlation measurement between the interferometer and the detector output leads. We also investigate a modified setup in which the detector is replaced by a two-path interferometer.We show that the path distinguishability and the visibility of the joint detection can be controlled in a continuous manner, and satisfy a complementarity relation for the entangled electrons.

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Kicheon Kang. 2006-07-05. An Electronic Mach-Zehnder Quantum Eraser. https://doi.org/10.1103/physrevb.75.125326

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