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arXiv · 1606.03682

Interlayer Resistance of Misoriented MoS2

Abstract

Interlayer misorientation in transition metal dichalcogenides alters the interlayer distance, the electronic band structure, and the vibrational modes, but, its effect on the interlayer resistance is not known. This work analyzes the coherent interlayer resistance of misoriented 2H-MoS2 for low energy electrons and holes as a function of the misorientation angle. The electronic interlayer resistance monotonically increases with the supercell lattice constant by several orders of magnitude similar to that of misoriented bilayer graphene. The large hole coupling gives low interlayer hole resistance that weakly depends on the misorientation angle. Interlayer rotation between an n-type region and a p-type region will suppress the electron current with little effect on the hole current. We estimate numerical bounds and explain the results in terms of the orbital composition of the bands at high symmetry points. Density functional theory calculations provide the interlayer coupling used in both a tunneling Hamiltonian and a non-equilibrium Green function calculation of the resistivity.

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Kuan Zhou, Darshana Wickramaratne, Supeng Ge, Shanshan Su, Amrit De, Roger K. Lake. 2016-06-12. Interlayer Resistance of Misoriented MoS2. https://doi.org/10.1039/c6cp08927e

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