1202.1344 (Marcos Flores et al.)

Moiré patterns on STM images of graphite from surface and subsurface
rotated layer    [PDF]

Marcos Flores, Patricio Vargas, Eduardo Cisternas

We have observed with STM moir\'e patterns corresponding to the rotation of
one graphene layer on HOPG surfaces. The moir\'e pattern domains were
characterized by rotation angle and extension in the plane. Additionally, by
identifying the border domain and defects we can discriminate between moir\'e
patterns due to rotation on the surface or subsurface layers. For a better
understanding of moir\'e pattern formation we have studied, from a theoretical
point of view, an array of three graphene layers where the top or middle layer
appears rotated around the stacking axis. By applying first-principles
total-energy electronic structure calculations to this array we obtain the
spatial charge density and its corresponding STM image. We compare the
experimental and theoretical results and show the strong influence of rotations
both in surface and subsurface layers for moir\'e pattern formations in HOPG
STM images.

View original: http://arxiv.org/abs/1202.1344