论文标题
二维双苯基网络中的磁有序，异常LIFSHITZ过渡和拓扑晶界
Magnetic Ordering, Anomalous Lifshitz Transition and Topological Grain Boundaries in Two-Dimensional Biphenylene Network
论文作者
论文摘要
我们研究通过联网双苯基分子形成的新平面碳晶体的电子特性。碳材料（例如区域中心鞍点和特殊的II型迪拉克费米子状态）中的新型电子特征显示在低能电子光谱中存在。 II型状态在这里具有几乎平坦的分支，并且接近向I型的过渡。讨论了与低能带有关的可能的磁不稳定性。此外，有了中等单轴菌株，一对Dirac点与区域中心鞍点合并，并实现了范霍夫奇异性的同时升级Lifshitz的过渡以及对Dirac Fermions的一对。构建了一个新的有效的汉密尔顿人，涵盖了所有独特的低能状态，揭示了围绕狄拉克点，量化的Zak阶段和拓扑晶界状态的有限绕组数量的伪造旋转纹理。
We study electronic properties of a new planar carbon crystal formed through networking biphenylene molecules. Novel electronic features among carbon materials such as zone-center saddle point and peculiar type-II Dirac fermionic states are shown to exist in the low energy electronic spectrum. The type-II state here has a nearly flat branch and is close to a transition to type-I. Possible magnetic instabilities related with low energy bands are discussed. Furthermore, with a moderate uniaxial strain, a pair of Dirac points merge with the zone center saddle point, realizing concurrent Lifshitz transitions of van Hove singularity as well as pair annihilation of the Dirac fermions. A new effective Hamiltonian encompassing all distinctive low energy states is constructed, revealing a finite winding number of the pseudo-spin texture around the Dirac point, quantized Zak phases, and topological grain boundary states.
