论文标题
在高阶范霍夫奇点存在下密度波的命运
Fate of density waves in the presence of a higher order van Hove singularity
论文作者
论文摘要
电子带结构中的拓扑转换，导致状态密度的范霍夫奇异性，可能会极大地影响量子材料中各种类型的订单。定期的拓扑转变（颈部形成或塌陷）导致状态的电子密度（DOS）的对数差异随二维中能量的函数。除了常规的Van Hove奇异性外，还有高级范霍夫奇异性（HOVH），DOS中有幂律分歧。通过采用重新归一化组（RG）技术，我们研究了由费米表面嵌套部分形成的旋转密度波相的命运，当时HOVHS并行出现。我们发现，随着奇点的存在的存在，临界温度通过数量级的升高来增强相位的形成。我们讨论了我们的发现可能应用于一系列量子材料，例如Sr $ _3 $ ru $ _2 $ o $ _7 $，sr $ _2 $ ruo $ _4 $和过渡金属二进制二物源。
Topological transitions in electronic band structures, resulting in van Hove singularities in the density of states, can considerably affect various types of orderings in quantum materials. Regular topological transitions (of neck formation or collapse) lead to a logarithmic divergence of the electronic density of states (DOS) as a function of energy in two-dimensions. In addition to the regular van Hove singularities, there are higher order van Hove singularities (HOVHS) with a power-law divergences in DOS. By employing renormalization group (RG) techniques, we study the fate of a spin-density wave phase formed by nested parts of the Fermi surface, when a HOVHS appears in parallel. We find that the phase formation can be boosted by the presence of the singularity, with the critical temperature increasing by orders of magnitude. We discuss possible applications of our findings to a range of quantum materials such as Sr$_3$Ru$_2$O$_7$, Sr$_2$RuO$_4$ and transition metal dichalcogenides.
