论文标题
并非所有掺杂的莫特绝缘子都有伪gap：van霍夫奇点的关键作用
Not all doped Mott insulators have a pseudogap: key role of van Hove singularities
论文作者
论文摘要
父母化合物的Mott绝缘阶段通常被视为不足的高$ T_C $ CUPRATE超导体的起点。特别是，伪态状态通常被认为是源自Mott绝缘体的。在这项工作中，我们系统地研究了正方形和三角形晶格上不同矮小的莫特绝缘子，以阐明伪群和莫特内斯之间的关系。我们表明，掺杂二维Mott绝缘子并不一定会导致伪群阶段。尽管具有固有的强耦合性质，但我们发现伪群的存在或不存在敏感地取决于非相互作用带参数，并确定了系统的Van Hove奇异性所起的关键作用。由伪态状态的su（2）量规理论激励，我们提出和验证一个简单的方程式，该方程控制了电子散射速率中特征特征的演变。
The Mott insulating phase of the parent compounds is frequently taken as starting point for the underdoped high-$T_c$ cuprate superconductors. In particular, the pseudogap state is often considered as deriving from the Mott insulator. In this work, we systematically investigate different weakly-doped Mott insulators on the square and triangular lattice to clarify the relationship between the pseudogap and Mottness. We show that doping a two-dimensional Mott insulator does not necessarily lead to a pseudogap phase. Despite its inherent strong-coupling nature, we find that the existence or absence of a pseudogap depends sensitively on non-interacting band parameters and identify the crucial role played by the van Hove singularities of the system. Motivated by a SU(2) gauge theory for the pseudogap state, we propose and verify numerically a simple equation that governs the evolution of characteristic features in the electronic scattering rate.
