2013/04/30 by José L. Lado, J. L. Lado, J. W. González +2 · 21 citations
Engineering · Materials Science · Physics and Astronomy · #Advancements in Semiconductor Devices and Circuit Design #Condensed matter physics #Conductance #Electron #Geometry #Graphene #Graphene research and applications #Heterojunction #Perpendicular #Physics #Quantization (signal processing) #Quantum Hall effect #Quantum and electron transport phenomena #Quantum mechanics #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.88.035448
published in Physical Review B 88(3) (American Physical Society) · 11 pages, 8 figures
arxiv created 2013/07/31 · openalex publication_date 2013/07/31 · arxiv updated 2013/08/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We model the quantum Hall effect in heterostructures made of two gapped graphene stripes with different gaps, \ensuremathΔ1 and \ensuremathΔ2. We consider two main situations, \ensuremathΔ1=0,\ensuremathΔ2\ensuremath≠0, and \ensuremathΔ1=\ensuremath-\ensuremathΔ2. They are different in a fundamental aspect: only the latter features kink states that, when intervalley coupling is absent, are protected against backscattering. We compute the two-terminal conductance of heterostructures with channel length up to 430 nm, in two transport configurations, parallel and perpendicular to the interface. By studying the effect of disorder on the transport along the boundary, we quantify the robustness of kink states with respect to backscattering. Transport perpendicular to the boundary shows how interface states open a backscattering channel for the conducting edge states, spoiling the perfect conductance quantization featured by the homogeneously gapped graphene Hall bars. Our results can be relevant for the study of graphene deposited on hexagonal boron-nitride, as well as to model graphene with an interaction-driven gapped phase with two equivalent phases separated by a domain wall.