中国物理B ›› 2017, Vol. 26 ›› Issue (2): 26502-026502.doi: 10.1088/1674-1056/26/2/026502

• CONDENSED MATTER: STRUCTURAL, MECHANICAL, AND THERMAL PROPERTIES • 上一篇    下一篇

Orbital electronic heat capacity of hydrogenated monolayer and bilayer graphene

Mohsen Yarmohammadi   

  1. Young Researchers and Elite Club, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran
  • 收稿日期:2016-10-12 修回日期:2016-11-11 出版日期:2017-02-05 发布日期:2017-02-05
  • 通讯作者: Mohsen Yarmohammadi E-mail:m.yarmohammadi69@gmail.com

Orbital electronic heat capacity of hydrogenated monolayer and bilayer graphene

Mohsen Yarmohammadi   

  1. Young Researchers and Elite Club, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran
  • Received:2016-10-12 Revised:2016-11-11 Online:2017-02-05 Published:2017-02-05
  • Contact: Mohsen Yarmohammadi E-mail:m.yarmohammadi69@gmail.com

摘要: The tight-binding Harrison model and Green's function approach have been utilized in order to investigate the contribution of hybridized orbitals in the electronic density of states (DOS) and electronic heat capacity (EHC) for four hydrogenated structures, including monolayer chair-like, table-like, bilayer AA- and finally AB-stacked graphene. After hydrogenation, monolayer graphene and bilayer graphene are behave as semiconducting systems owning a wide direct band gap and this means that all orbitals have several states around the Fermi level. The energy gap in DOS and Schottky anomaly in EHC curves of these structures are compared together illustrating the maximum and minimum band gaps are appear for monolayer chair-like and bilayer AA-stacked graphane, respectively. In spite of these, our findings show that the maximum and minimum values of Schottky anomaly appear for hydrogenated bilayer AA-stacked and monolayer table-like configurations, respectively.

关键词: hydrogenated monolayer and bilayer graphene, Harrison model, electronic heat capacity, density of states, Green', s function

Abstract: The tight-binding Harrison model and Green's function approach have been utilized in order to investigate the contribution of hybridized orbitals in the electronic density of states (DOS) and electronic heat capacity (EHC) for four hydrogenated structures, including monolayer chair-like, table-like, bilayer AA- and finally AB-stacked graphene. After hydrogenation, monolayer graphene and bilayer graphene are behave as semiconducting systems owning a wide direct band gap and this means that all orbitals have several states around the Fermi level. The energy gap in DOS and Schottky anomaly in EHC curves of these structures are compared together illustrating the maximum and minimum band gaps are appear for monolayer chair-like and bilayer AA-stacked graphane, respectively. In spite of these, our findings show that the maximum and minimum values of Schottky anomaly appear for hydrogenated bilayer AA-stacked and monolayer table-like configurations, respectively.

Key words: hydrogenated monolayer and bilayer graphene, Harrison model, electronic heat capacity, density of states, Green's function

中图分类号:  (Heat capacity)

  • 65.40.Ba
73.22.Pr (Electronic structure of graphene) 65.80.Ck (Thermal properties of graphene) 74.20.Pq (Electronic structure calculations)