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arXiv · 0910.5693

Neutral modes edge state dynamics through quantum point contacts

Dario Ferraro·Alessandro Braggio·Nicodemo Magnoli·Maura Sassetti
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Abstract

Dynamics of neutral modes for fractional quantum Hall states is investigated for a quantum point contact geometry in the weak-backscattering regime. The effective field theory introduced by Fradkin-Lopez for edge states in the Jain sequence is generalized to the case of propagating neutral modes. The dominant tunnelling processes are identified also in the presence of non-universal phenomena induced by interactions. The crossover regime in the backscattering current between tunnelling of single-quasiparticles and of agglomerates of p-quasiparticles is analysed. We demonstrate that higher order cumulants of the backscattering current fluctuations are a unique resource to study quantitatively the competition between different carrier charges. We find that propagating neutral modes are a necessary ingredient in order to explain this crossover phenomena.

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Dario Ferraro, Alessandro Braggio, Nicodemo Magnoli, Maura Sassetti. 2009-10-29. Neutral modes edge state dynamics through quantum point contacts. https://doi.org/10.1088/1367-2630%2F12%2F1%2F013012

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