Observation and interpretation of adjacent Moire patterns of different shapes in bilayer graphene

In transmission electron micrography of few-layer thick graphene samples, two distinct regions, a region of superlattice and an adjacent region of parallel straight bands, are seen. These two features are explained as Moire patterns produced by (1) rotation of top part of one of the graphene layers and (2) a small change in the shape of the bottom part of the same layer. It is interesting to note that for the first time, Moire pattern of parallel straight bands is observed and satisfactorily explained. (C) 2011 American Institute of Physics. [doi:10.1063/1.3624703]