Instabilities of a birefringent semimetal
Instabilities of a birefringent semimetal
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DOI：
10.1103/physrevb.90.045131
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发表时间：
2014-05
影响因子：
3.7
通讯作者：
Nazanin Komeilizadeh;M. Kennett
中科院分区：
文献类型：
--
作者：
Nazanin Komeilizadeh;M. Kennett
双折射费米子是在正方形晶格上的无自旋费米子的一种特殊紧束缚模型的无质量费米子低能激发中产生的，这种模型具有两种“光速”[M. P.肯内特，${\it\，al.}$，Phys. Rev. A ${\bf 83}$，053636（2011）]。我们使用平均场理论来研究相位时，可能会出现在这个模型中有最近的邻居和下一个最近的邻居排斥相互作用和弱相互作用的存在下，双折射半金属相的鲁棒性，并确定过渡到交错密度和量子异常霍尔有序相。我们考虑耦合双折射费米子的磁场的影响，并找到相应的朗道水平的解析表达式，并证明其整数量子霍尔效应显示额外的平台超出常规狄拉克费米子，如在石墨烯中观察到的。我们简要地讨论了紧束缚结构，导致三维双折射费米子。
Birefringent fermions arise as massless fermionic low energy excitations of a particular tight binding model for spinless fermions on a square lattice which have two "speeds of light" [M. P. Kennett, ${\it et \, al.}$, Phys. Rev. A ${\bf 83}$, 053636 (2011)]. We use mean field theory to study phases that can arise when there are nearest neighbour and next-nearest neighbour repulsive interactions in this model and demonstrate robustness of the birefringent semi-metal phase in the presence of weak interactions and identify transitions to staggered density and quantum anomalous Hall ordered phases. We consider the effect of coupling birefringent fermions to a magnetic field, and find analytic expressions for the corresponding Landau levels and demonstrate that their integer Quantum Hall effect displays additional plateaux beyond those observed for regular Dirac fermions, such as in graphene. We briefly discuss a tight-binding construction that leads to three dimensional birefringent fermions.