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Hexagonal boron nitride (hBN) isa natural hyperbolic material,which can also accommodate highly dispersive surface phonon-polaritonmodes. In this paper, we examine theoretically the mid-infrared opticalproperties of graphene–hBN heterostructures derived from theircoupled plasmon–phonon modes. We find that the graphene plasmoncouples differently with the phonons of the two Reststrahlen bands,owing to their different hyperbolicity. This also leads to distinctivelydifferent interaction between an external quantum emitter and theplasmon–phonon modes in the two bands, leading to substantialmodification of its spectrum. The coupling to graphene plasmons allowsfor additional gate tunability in the Purcell factor and narrow dipsin its emission spectra. [ABSTRACT FROM AUTHOR]

Recent experiments show that a substantial energy gap in graphene can be induced via patterned hydrogenation on an iridium substrate. Here, we show that the energy gap is roughly proportional to NH1/2/NCwhen disorder is accounted for, where NHand NCdenote concentrations of hydrogen and carbon atoms, respectively. The dispersion relation, obtained through calculation of the momentum-energy resolved density of states, is shown to agree with previous angle-resolved photoemission spectroscopy results. Simulations of electronic transport in finite size samples also reveal a similar transport gap, up to 1 eV within experimentally achievable NH1/2/NCvalues. [ABSTRACT FROM AUTHOR]

Graphene has been proposed as a promising material for future nanoelectronics because of its unique electronic properties. Understanding the scaling behavior of this new nanomaterial under common experimental conditions is of critical importance for developing graphene-based nanoscale devices. We present a comprehensive experimental and theoretical study on the influence of edge disorder and bulk disorder on the minimum conductivity of graphene ribbons. For the first time, we discovered a strong nonmonotonic size scaling behavior featuring a peak and saturation minimum conductivity. Through extensive numerical simulations and analysis, we are able to attribute these features to the amount of edge and bulk disorder in graphene devices. This study elucidates the quantum transport mechanisms in realistic experimental graphene systems, which can be used as a guideline for designing graphene-based nanoscale devices with improved performance. [ABSTRACT FROM AUTHOR]

Particular strain geometry in graphene could lead to a uniform pseudomagnetic field of order 10Tand might open up interesting applications in graphene nanoelectronics. Through quantum transport calculations of realistic strained graphene flakes of sizes of 100 nm, we examine possible means of exploiting this effect for practical electronics and valleytronics devices. First, we found that elastic backscattering at rough edges leads to the formation of well-defined transport gaps of order 100 meV under moderate maximum strain of 10%. Second, the application of a real magnetic field induced a separation, in space and energy, of the states arising from different valleys, leading to a way of inducing bulk valley polarization which is insensitive to short-range scattering. [ABSTRACT FROM AUTHOR]