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arXiv · 1907.00532

Negative Excess Shot Noise by Anyon Braiding

Byeongmok Lee·Cheolhee Han·H. -S. Sim
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Abstract

Anyonic fractional charges $e^*$ have been detected by autocorrelation shot noise at a quantum point contact (QPC) between two fractional quantum Hall edges. We find that the autocorrelation noise can also show a fingerprint of Abelian anyonic fractional statistics. We predict the noise of electrical tunneling current $I$ at the QPC of the fractional-charge detection setup, when anyons are dilutely injected, from an additional edge biased by a voltage, to the setup in equilibrium. At large voltages, the nonequilibrium noise is {\it reduced} below the thermal equilibrium noise by the value $2 e^* I$. This negative excess noise is opposite to the positive excess noise $2e^* I$ of the conventional fractional-charge detection and also to usual positive autocorrelation noises of electrical currents. This is a signature of the Abelian fractional statistics, resulting from the effective braiding of an anyon thermally excited at the QPC around another anyon injected from the additional edge.

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Byeongmok Lee, Cheolhee Han, H. -S. Sim. 2019-07-01. Negative Excess Shot Noise by Anyon Braiding. https://doi.org/10.1103/physrevlett.123.016803

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