论文标题
狄拉克半分cesbte中的电荷密度波和弱临床效应
Charge density wave and weak Kondo effect in a Dirac semimetal CeSbTe
论文作者
论文摘要
使用角度分辨光发射光谱（ARPE）和低能电子衍射（LEED），以及密度功能理论（DFT）计算，我们报告了电荷密度波（CDW）的形成及其与Cesbte中近距离效应和拓扑状态的相互作用。观察到的费米表面（FS）表现出可以通过观察到的CDW排序矢量很好地连接的平行段，这表明CDW顺序是由嵌套FS的Electron-Phonon耦合（EPC）驱动的。 CDW间隙是较大（〜0.3 eV）和动量依赖性的，这自然会解释到高温为高温的强大CDW顺序。缝隙开口导致在费米水平（EF）附近的状态密度（DOS）降低，这相应地抑制了多体刚多效应，从而导致在20 K及以上的局部局部4F电子。发现X点处的拓扑狄拉克锥在CDW阶段内保持无间隙。我们的结果为CDW与近托晶格系统中的昆多效应之间的竞争提供了证据。 CESBTE和相关化合物中强大的CDW顺序为搜索长期轴心绝缘体提供了机会。
Using angle-resolved photoemission spectroscopy (ARPES) and low-energy electron diffraction (LEED), together with density-functional theory (DFT) calculation, we report the formation of charge density wave (CDW) and its interplay with the Kondo effect and topological states in CeSbTe. The observed Fermi surface (FS) exhibits parallel segments that can be well connected by the observed CDW ordering vector, indicating that the CDW order is driven by the electron-phonon coupling (EPC) as a result of the nested FS. The CDW gap is large (~0.3 eV) and momentum-dependent, which naturally explains the robust CDW order up to high temperatures. The gap opening leads to a reduced density of states (DOS) near the Fermi level (EF), which correspondingly suppresses the many-body Kondo effect, leading to very localized 4f electrons at 20 K and above. The topological Dirac cone at the X point is found to remain gapless inside the CDW phase. Our results provide evidence for the competition between CDW and the Kondo effect in a Kondo lattice system. The robust CDW order in CeSbTe and related compounds provide an opportunity to search for the long-sought-after axionic insulator.
