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arXiv · 0806.1211

Universal dephasing in a chiral 1D interacting fermion system

Clemens Neuenhahn·Florian Marquardt
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Abstract

We consider dephasing by interactions in a one-dimensional chiral fermion system (e.g. a Quantum Hall edge state). For finite-range interactions, we calculate the spatial decay of the Green's function at fixed energy, which sets the contrast in a Mach-Zehnder interferometer. Using a physically transparent semiclassical ansatz, we find a power-law decay of the coherence at high energies and zero temperature (T=0), with a universal asymptotic exponent of 1, independent of the interaction strength. We obtain the dephasing rate at T>0 and the fluctuation spectrum acting on an electron.

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Clemens Neuenhahn, Florian Marquardt. 2009-03-17. Universal dephasing in a chiral 1D interacting fermion system. https://doi.org/10.1103/physrevlett.102.046806

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