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arXiv · 1606.08574

Decoherence of high-energy electrons in weakly disordered quantum Hall edge states

Simon E. Nigg·Anders Mathias Lunde
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Abstract

We investigate theoretically the phase coherence of electron transport in edge states of the integer quantum Hall effect at filling factor $ν=2$, in the presence of disorder and inter-edge state Coulomb interaction. Within a Fokker-Planck approach, we calculate analytically the visibility of the Aharonov-Bohm oscillations of the current through an electronic Mach-Zehnder interferometer. In agreement with recent experiments, we find that the visibility is independent of the energy of the current-carrying electrons injected high above the Fermi sea. Instead, it is the amount of disorder at the edge that sets the phase space available for inter-edge state energy exchange and thereby controls the visibility suppression.

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Simon E. Nigg, Anders Mathias Lunde. 2016-06-28. Decoherence of high-energy electrons in weakly disordered quantum Hall edge states. https://doi.org/10.1103/physrevb.94.041407

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