论文标题
在各向同性Luttinger半法的非Fermi液相中运输
Transport in the non-Fermi liquid phase of isotropic Luttinger semimetals
论文作者
论文摘要
Luttinger半法在三个空间维度的布里渊区中心具有二次带交叉。描述这些系统的模型中的库仑相互作用稳定了与非Fermi液态相关的非平凡固定点，也称为Luttinger-Abrikosov-Beneslavskii相。我们分别通过Kubo公式和Mori-Zwanzig内存矩阵方法来计算此阶段的光电率$σ（ω）$和DC电导率$σ_{DC}（t）$。有趣的是，我们发现$σ（ω）$作为应用AC电场的频率$ω$的函数，其特征是在干净限制中对超标准属性的小侵犯，这与具有dirac quasiparticles在激发光谱和OBEY Hyperscalcalscalscalcalscalscalscal中具有的低能有效理论形成了鲜明对比。此外，与清洁极限相比，弱短距离疾病对$σ_{dc}（t）$温度依赖性的影响会在低温下引起更强的幂律抑制。我们的发现表明，这些无序系统实际上是幂律绝缘子。我们的理论结果与在luttinger半分化合物（如pyrochlore iridates [（y $ _ $ _ {1-x} $ pr $ _x $）$ _ 2 $ _2 $ ir $ $ _2 $ o $ _7 $的数据中，来自Luttinger半分化合物的最新实验数据一致。
Luttinger semimetals have quadratic band crossings at the Brillouin zone-center in three spatial dimensions. Coulomb interactions in a model that describes these systems stabilize a non-trivial fixed point associated with a non-Fermi liquid state, also known as the Luttinger-Abrikosov-Beneslavskii phase. We calculate the optical conductivity $σ(ω) $ and the dc conductivity $σ_{dc} (T) $ of this phase, by means of the Kubo formula and the Mori-Zwanzig memory matrix method, respectively. Interestingly, we find that $σ(ω) $, as a function of the frequency $ω$ of an applied ac electric field, is characterized by a small violation of the hyperscaling property in the clean limit, which is in marked contrast to the low-energy effective theories that possess Dirac quasiparticles in the excitation spectrum and obey hyperscaling. Furthermore, the effects of weak short-ranged disorder on the temperature-dependence of $σ_{dc} (T)$ give rise to a much stronger power-law suppression at low temperatures compared to the clean limit. Our findings demonstrate that these disordered systems are actually power-law insulators. Our theoretical results agree qualitatively with the data from recent experiments performed on Luttinger semimetal compounds like the pyrochlore iridates [ (Y$_{1-x}$Pr$_x$)$_2$Ir$_2$O$_7$ ].
