Fine structure of the local pseudogap and Fano effect for superconducting electrons near a zigzag graphene edge

Grigory Tkachov

doi:10.1103/physrevb.76.235409

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arXiv · 0707.3048

Fine structure of the local pseudogap and Fano effect for superconducting electrons near a zigzag graphene edge

Grigory Tkachov

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Abstract

Motivated by recent scanning tunneling experiments on zigzag-terminated graphene this paper investigates an interplay of evanescent and extended quasiparticle states in the local density of states (LDOS) near a zigzag edge using the Green's function of the Dirac equation. A model system is considered where the local electronic structure near the edge influences transport of both normal and superconducting electrons via a Fano resonance. In particular, the temperature enhancement of the critical Josephson current and 0-pi transitions are predicted.

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Grigory Tkachov. 2007-11-16. Fine structure of the local pseudogap and Fano effect for superconducting electrons near a zigzag graphene edge. https://doi.org/10.1103/physrevb.76.235409

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