Communications in Theoretical Physics ›› 2017, Vol. 67 ›› Issue (05): 569-576.

• Condensed Matter: Electronic Structure, Electrical, Magnetic, and Optical Properties • Previous Articles     Next Articles

Controlling Thermodynamic Properties of Ferromagnetic Group-IV Graphene-Like Nanosheets by Dilute Charged Impurity

Mohsen Yarmohammadi, Kavoos Mirabbaszadeh   

  1. Department of Energy Engineering and Physics, Amirkabir University of Technology, Tehran, Iran
  • Received: 2016-09-26 Revised: 2017-01-13 Published: 2017-05-01
  • Contact: Mohsen Yarmohammadi,E-mail:m.yarmohammadi69@gmail.com E-mail:m.yarmohammadi69@gmail.com

Abstract: Using the Kane-Mele Hamiltonian, Dirac theory and self-consistent Born approximation, we investigate the effect of dilute charged impurity on the electronic heat capacity and magnetic susceptibility of two-dimensional ferromagnetic honeycomb structure of group-IV elements including silicene, germanene and stanene within the Green's function approach. We also find these quantities in the presence of applied external electric field. Our results show that the silicene (stanene) has the maximum (minimum) heat capacity and magnetic susceptibility at uniform electric fields. From the behavior of theses quantities, the band gap has been changed with impurity concentration, impurity scattering strength and electric field. The analysis on the impurity-dependent magnetic susceptibility curves shows a phase transition from ferromagnetic to paramagnetic and antiferromagnetic phases. Interestingly, electronic heat capacity increases (decreases) with impurity concentration in silicene (germanene and stanene) structure.

Key words: ferromagnetic group-IV elements, Green's function, electronic heat capacity, magnetic susceptibility, phase transition

PACS numbers: 

  • 65.40.Ba