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Dephasing due to Which Path Detector

E. Buks·R. Schuster·M. Heiblum·D. Mahalu·V. Umansky
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Abstract

We study dephasing of electrons induced by a which path detector and thus verify Bohr's complementarity principle for fermions. We utilize a double path interferometer with two slits, with one slit being replaced by a coherent quantum dot (QD). A short one dimensional channel, in the form of a quantum point contact (QPC), in close proximity to the QD, serves as a which path detector. We find that by varying the properties of the QPC detector we affect the visibility of the interference, inducing thus dephasing. We develop a simple model to explain the dephasing due to the nearby detector and find good agreement with the experiment.

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E. Buks, R. Schuster, M. Heiblum, D. Mahalu, V. Umansky. 1997-09-10. Dephasing due to Which Path Detector. https://doi.org/10.1016/s0921-4526(98)00118-5

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