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arXiv · 1904.00918

Semimetallic features in quantum transport through a gate-defined point contact in bilayer graphene

Thomas L M Lane·Angelika Knothe·Vladimir I Fal'ko
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Abstract

We demonstrate that, at the onset of conduction, an electrostatically defined quantum wire in bilayer graphene (BLG) with an interlayer asymmetry gap may act as a 1D semimetal, due to the multiple minivalley dispersion of its lowest subband. Formation of a non-monotonic subband coincides with a near-degeneracy between the bottom edges of the lowest two subbands in the wire spectrum, suggesting an $8e^2/h$ step at the conduction threshold, and the semimetallic behaviour of the lowest subband in the wire would be manifest as resonance transmission peaks on an $8e^2/h$ conductance plateau.

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Thomas L M Lane, Angelika Knothe, Vladimir I Fal'ko. 2019-06-24. Semimetallic features in quantum transport through a gate-defined point contact in bilayer graphene. https://doi.org/10.1103/physrevb.100.115427

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