Disappearance of the Dirac cone in silicene due to the presence of an electric field

作     者：D.A.Rowlands 张宇钟 

作者机构：Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology School of Physics Science and EngineeringTongji University 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2014年第23卷第3期

页      面：63-70页

核心收录：

学科分类：0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 

基　　金：Project supported by the National Natural Science Foundation of China (Grant No. 11174219) the Program for New Century Excellent Talents in Universities,China (Grant No. NCET-13-0428) the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20110072110044) the Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning, China the Scientific Research Foundation for the Returned Overseas Chinese Scholars of the Education Ministry of China 

主　　题：silicene Dirac cone ionic Hubbard model coherent-potential approximation 

摘      要：Using the two-dimensional ionic Hubbard model as a simple basis for describing the electronic structure of silicene in the presence of an electric field induced by the substrate, we use the coherent-potential approximation to calculate tbe zero-temperature phase diagram and the associated spectral function at half filling. We find that any degree of symmetry- breaking induced by the electric field causes the silicene structure to lose its Dirac fermion characteristics, thus providing a simple mechanism for the disappearance of the Dirac cone.