Anisotropic flat bands on the surface of multilayer graphenelike lattice
A. A. Zyuzin+*, V. A. Zyuzin×
+Department of Physics, University of Basel, CH-4056 Basel, Switzerland
*Ioffe Physico-Technical Institute of the RAS, 194021 St. Petersburg, Russia
×Department of Physics, University of Florida, FL 32611-8440 Gainesville, USA
Abstract
The fermionic energy spectrum on the surface of the multilayer honeycomb
lattice with rhombohedral stacking has topologically protected flat bands.
It is shown that topological phase transition occurs in the anisotropic
multilayer graphene-like structure with strongly anisotropic intra-layer
coupling,
at which two flat bands with opposite chirality merge into one and split,
opening up a gap in the energy spectrum, depending on the anisotropy of the
intralayer hopping.
The dispersion of the flat bands of the multilayer is anisotropic and the
density of states is more singular in the vicinity of the transition.