2014/06/30 by Matthieu Bellec, Ulrich Kuhl, Gilles Montambaux +1
Physics and Astronomy · #cond-mat.mes-hall
paper · pdf · doi:10.1088/1367-2630/16/11/113023
published as New Journal of Physics 16 (2014) 113023 · 15 pages, 9 figures
arxiv created 2014/12/09 · arxiv updated 2014/12/10
Edge states are one important ingredient to understand transport properties of graphene nanoribbons. We study experimentally the existence and the internal structure of edge states under uniaxial strain of the three main edges: zigzag, bearded, and armchair. The experiments are performed on artificial microwave graphene flakes, where the wavefunctions are obtained by direct imaging. We show that uniaxial strain can be used to manipulate the edge states: a single parameter controls their existence and their spatial extension into the ribbon. By combining tight-binding approach and topological arguments, we provide an accurate description of our experimental findings. A new type of zero-energy state appearing at the intersection of two edges, namely the corner state, is also observed and discussed.