Anomalous charge tunneling in the fractional quantum Hall edge states at filling factor ν= 5/2

M. Carrega; D. Ferraro; A. Braggio; N. Magnoli; M. Sassetti

doi:10.1103/physrevlett.107.146404

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arXiv · 1102.5666

Anomalous charge tunneling in the fractional quantum Hall edge states at filling factor ν= 5/2

M. Carrega·D. Ferraro·A. Braggio·N. Magnoli·M. Sassetti

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Abstract

We explain effective charge anomalies recently observed for fractional quantum Hall edge states at $ν=5/2$ [M. Dolev, Y. Gross, Y. C. Chung, M. Heiblum, V. Umansky, and D. Mahalu, Phys.Rev. B. \textbf{81}, 161303(R) (2010)]. The experimental data of differential conductance and excess noise are fitted, using the anti-Pfaffian model, by properly take into account renormalizations of the Luttinger parameters induced by the coupling of the system with an intrinsic $1/f$ noise. We demonstrate that a peculiar agglomerate excitation with charge $e/2$, double of the expected $e/4$ charge, dominates the transport properties at low energies.

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M. Carrega, D. Ferraro, A. Braggio, N. Magnoli, M. Sassetti. 2011-09-30. Anomalous charge tunneling in the fractional quantum Hall edge states at filling factor ν= 5/2. https://doi.org/10.1103/physrevlett.107.146404

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