Effective hopping between magnetic impurities in silicene

Abstract

In this work we analyze the effects of the conduction electrons on the hopping function between two magnetic impurities located in the A sublattice in silicene placed in an external electric field. By using the Schrieffer-Wolff transformation we analyze the dependence of the effective hopping on the distance between the magnetic adatoms. By using particle number conservation, the spectrum for different occupation numbers is studied for different values of the Hubbard parameter, the electric field and the inter-impurity distance. We show that for half-filling an ionic to covalent ground state transition and viceversa can be achieved for a specific electric field strength. Finally, we explore the partition function and we study the average energy and average occupation as a function of temperature, obtaining a pattern of Mott plateaus.