北京师范大学学报（自然科学版）2023，Vol.59Issue(6)：926-933,8.DOI:10.12202/j.0476-0301.2023189
塞曼场下狄拉克费米子系统的输运与磁序转变
Transport and magnetic transition of Dirac fermion systems in Zeeman field
摘要
Abstract
Since Slater suggested that a gap could be opened by magnetic ordering with spin-dependent electronic energy,applying magnetic field has been a powerful means to tune properties of Dirac fermion systems,especially of the 2D graphene system.Determinant quantum Monte Carlo(DQMC)method is used,to investigate phase transitions induced by Zeeman field in 2D graphene lattice.Competition between Coulomb repulsion U,disorder ⊿ and magnetic fields B drives semimetallic regime to insulating phases exhibiting different characters.Further,critical Zeeman field Bc triggering band-insulator is largely reduced by the presence of interaction and disorder.As magnetic field continues to increase,B-induced symmetry breaking introduces an antiferromagnetic(AFM)phase,and eventually the system enters a fully spin-polarized state.In correlated system,weak interaction would enhance the effect of magnetic field on AFM phase,while strong interaction larger than Uc=4.5 would inhibit this effect.Applying parallel magnetic fields provides the possibility to observe transport and magnetic transitions in real materials.关键词
石墨烯/塞曼场/Hubbard模型/行列式量子蒙特卡罗(DQMC)方法Key words
graphene/Zeeman field/Hubbard model/determinant quantum Monte Carlo(DQMC)method分类
物理学引用本文复制引用
孟敬尧,郭恺怡,梁颖..塞曼场下狄拉克费米子系统的输运与磁序转变[J].北京师范大学学报（自然科学版）,2023,59(6):926-933,8.基金项目
国家自然科学基金资助项目(11974049) （11974049）
