Robustness of edge states in graphene quantum dots
Abstract
We analyze the singleparticle states at the edges of disordered graphene quantum dots. We show that generic graphene quantum dots support a number of edge states proportional to circumference of the dot over the lattice constant. Our analytical theory agrees well with numerical simulations. Perturbations breaking electronhole symmetry such as nextnearestneighbor hopping or edge impurities shift the edge states away from zero energy but do not change their total amount. We discuss the possibility of detecting the edge states in an antidot array and provide an upper bound on the magnetic moment of a graphene dot.
 Publication:

Physical Review B
 Pub Date:
 July 2010
 DOI:
 10.1103/PhysRevB.82.045409
 arXiv:
 arXiv:1003.4602
 Bibcode:
 2010PhRvB..82d5409W
 Keywords:

 73.21.La;
 73.22.Pr;
 73.20.At;
 73.22.f;
 Quantum dots;
 Surface states band structure electron density of states;
 Electronic structure of nanoscale materials: clusters nanoparticles nanotubes and nanocrystals;
 Condensed Matter  Mesoscale and Nanoscale Physics
 EPrint:
 Added figure 6, extended discussion (version as accepted by Physical Review B)