论文标题
Sublattice干扰促进Kagome金属中的对密度波顺序
Sublattice Interference promotes Pair Density Wave order in Kagome Metals
论文作者
论文摘要
由在局部排斥相互作用的情况下，在Kagome Metal CSV $ {} _ 3 $ sb $ {} _ 5 $中观察到的kagome金属CSV $ {} _ 3 $ sb $ {} _ 5 $的动机是由电子命运（VHS）附近的电子命运。我们研究了这种相互作用对vhs的费米表面“斑块”的影响。我们展示了称为Sublattice干扰的Kagome晶格的特征如何影响斑块之间的相互作用形式。此类互动的重新归一化组（RG）流导致最近的邻居交互$ v $超过现场排斥$ u $。我们确定这种情况有利于形成电荷密度波（CDW）和PDW订单。在弱耦合极限中，我们发现一个复杂的CDW顺序是领先的不稳定性，它破坏了时间逆转对称性。除了RG之外，我们还对仅$ V $的模型进行了Hartree-fock研究，并找到了在某些中间耦合处的配对密度波订单。
Motivated by the observation of a pair density wave (PDW) in the kagome metal CsV${}_3$Sb${}_5$, we consider the fate of electrons near a p-type van Hove singularity (vHS) in the presence of local repulsive interactions. We study the effect of such interactions on Fermi surface "patches" at the vHS. We show how a feature unique to the Kagome lattice known as sublattice interference crucially affects the form of the interactions among the patches. The renormalization group (RG) flow of such interactions results in a regime where the nearest neighbor interaction $V$ exceed the onsite repulsion $U$. We identify this condition as being favorable for the formation of charge-density-wave (CDW) and PDW orders. In the weak coupling limit, we find a complex CDW order as the leading instability, which breaks time reversal symmetry. Beyond RG, we perform a Hartree-Fock study to a $V$-only model and find the pair-density-wave order indeed sets in at some intermediate coupling.
