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arXiv · 1802.08100

Negative differential resistance in Van der Waals heterostructures due to moir\'{e}-induced spectral reconstruction

D. J. Leech·J. J. P. Thompson·M. Mucha-Kruczyński
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Abstract

Formation of moir\'{e} superlattices is common in Van der Waals heterostructures as a result of the mismatch between lattice constants and misalignment of crystallographic directions of the constituent two-dimensional crystals. We discuss theoretically electron transport in a Van der Waals tunnelling transistor in which one of the electrodes is made of two crystals forming a moir\'{e} superlattice at their interface. By investigating structures containing either the aligned graphene/hexagonal boron nitride heterostructure or twisted bilayer graphene, we show that negative differential resistance is possible in such transistors as a consequence of the superlattice-induced changes in the electronic density of states and without the need of momentum conserving tunnelling present in high-quality exfoliated devices.

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D. J. Leech, J. J. P. Thompson, M. Mucha-Kruczyński. 2018-02-22. Negative differential resistance in Van der Waals heterostructures due to moir\'{e}-induced spectral reconstruction. https://doi.org/10.1103/physrevapplied.10.034014

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