Physical Properties of the Spin Hamiltonian on Honeycomb Lattice Samples   with Kekul\'e and Vacuum Polarization Corrections
  Magnetic and thermodynamical properties of a system of spins in a honeycomb lattice, such as magnetization, magnetic susceptibility and specific heat, in a low-temperature regime are investigated by considering the effects of a Kekul\'e scalar exchange and QED vacuum polarization corrections to the interparticle potential. The spin lattice calculations are carried out by means of Monte Carlo simulations. We present a number of comparative plots of all the physical quantities we have considered and a detailed analysis is presented to illustrate the main features and the variation profiles of the properties with the applied external magnetic field and temperature. 
Ricardo S. Martins, Elena Konstantinova, Humberto Belich, Jos\'e A.   Helay\"el-Neto
cond-mat.mes-hall hep-th