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We propose an efficient numerical method to study the transport properties of armchair graphene ribbons in the presence of a generic external potential. The method is based on a continuum envelope-function description with physical boundary conditions. The envelope functions are computed in the reciprocal space, and the transmission is then obtained with a(More)
Investigating the structure of quantized plateaus in the Hall conductance of graphene is a powerful way of probing its crystalline and electronic structure and will also help to establish whether graphene can be used as a robust standard of resistance for quantum metrology. We use low-temperature scanning gate microscopy to image the interplateau breakdown(More)
Research in graphene-based electronics is recently focusing on devices based on vertical heterostructures of two-dimensional materials. Here we use density functional theory and multiscale simulations to investigate the tunneling properties of single- and double-barrier structures with graphene and few-layer hexagonal boron nitride (h-BN) or hexagonal boron(More)
We investigate the intrinsic performance of vertical and lateral graphene-based heterostructure field-effect transistors, currently considered the most promising options to exploit graphene properties in post-CMOS electronics. We focus on three recently proposed graphene-based transistors, that in experiments have exhibited large current modulation. Our(More)
We compare the performance prospects of three recently proposed and demonstrated transistors based on vertical and lateral graphene-based heterostructures, with the requirements of the International Technology Roadmap for Semiconductors. All devices provide large Ion/Ioff ratios, but only the lateral heterostructure field-effect transistors exhibit(More)
We propose a model for the numerical simulation of a two-terminal scanning gate spectroscopy experiment on bilayer graphene in the Quantum Hall regime. We start from the Chalker-Coddington random network model and link the model parameters with some of the relevant quantities in the experimental setup. The comparison between the simulation and the(More)
We compute, using a continuum model based on the Dirac equation, the transverse modes and the longitudinal wave vectors in an armchair ribbon, in the presence of a transversally variable external potential. We show that the application of a standard finite difference method to this problem is not effective, since it can lead to the appearance of spurious(More)
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