Enhancement of gaps in thin graphitic films for heterostructure formation

Article

关键词: 2-DIMENSIONAL HOLSTEIN MODEL;    CHARGE-DENSITY-WAVE;    ELECTRONIC-STRUCTURE;    BANDGAP;    SUPERCONDUCTIVITY;    DYNAMICS;    GRAPHENE;    VERTEX;   

DOI  :  10.1103/PhysRevB.89.155415

来源: SCIE

【 摘 要 】

There are a large number of atomically thin graphitic films with a structure similar to that of graphene. These films have a spread of band gaps relating to their ionicity and, also, to the substrate on which they are grown. Such films could have a range of applications in digital electronics, where graphene is difficult to use. I use the dynamical cluster approximation to show how electron-phonon coupling between film and substrate can enhance these gaps in a way that depends on the range and strength of the coupling. It is found that one of the driving factors in this effect is a charge density wave instability for electrons on a honeycomb lattice that can open a gap in monolayer graphene. The enhancement at intermediate coupling is sufficiently large that spatially varying substrates and superstrates could be used to create heterostructures in thin graphitic films with position-dependent electron-phonon coupling and gaps, leading to advanced electronic components.

【 授权许可】

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