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arXiv · 2012.03570

Superballistic electron flow through a point contact in a Ga[Al]As heterostructure

Lev V. Ginzburg·Carolin Gold·Marc P. Röösli·Christian Reichl·Matthias Berl·Werner Wegscheider·Thomas Ihn·Klaus Ensslin
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Abstract

We measure electronic transport through point contacts in the high-mobility electron gas in a Ga[Al]As heterostructure at different temperatures and bulk electron densities. The conductance through all point contacts increases with increasing temperature in a temperature window around $T \sim 10 K$ for all investigated electron densities and point contact widths. For high electron densities this conductance exceeds the fundamental ballistic limit (Sharvin limit). These observations are in agreement with a viscous electron transport model and previous experiments in graphene.

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Lev V. Ginzburg, Carolin Gold, Marc P. Röösli, Christian Reichl, Matthias Berl, Werner Wegscheider, Thomas Ihn, Klaus Ensslin. 2021-06-02. Superballistic electron flow through a point contact in a Ga[Al]As heterostructure. https://doi.org/10.1103/physrevresearch.3.023033

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