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arXiv · 1302.2670

Equilibration of quantum Hall edge states by an Ohmic contact

Artur O. Slobodeniuk·Ivan P. Levkivskyi·Eugene V. Sukhorukov
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Abstract

Ohmic contacts are crucial elements of electron optics that have not received a clear theoretical description yet. We propose a model of an Ohmic contact as a piece of metal of the finite capacitance $C$ attached to a quantum Hall edge. It is shown that charged quantum Hall edge states may have weak coupling to neutral excitations in an Ohmic contact. Consequently, despite being a reservoir of neutral excitations, an Ohmic contact is not able to efficiently equilibrate edge states if its temperature is smaller than $\hbar\Omega_c$, where $\Omega_c$ is the inverse RC time of the contact. This energy scale for a floating contact may become as large as the single-electron charging energy $e^2/ C$.

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Artur O. Slobodeniuk, Ivan P. Levkivskyi, Eugene V. Sukhorukov. 2013-02-11. Equilibration of quantum Hall edge states by an Ohmic contact. https://doi.org/10.1103/physrevb.88.165307

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