论文标题
电荷密度波，混乱和超导性的相互作用在2 $ h $ tase $ _2 $ nmr阐明
Interplay of charge density waves, disorder, and superconductivity in 2$H$-TaSe$_2$ elucidated by NMR
论文作者
论文摘要
通过$^{77} $ se核磁共振（NMR）研究了原始的原始晶体和6％PD交换2H-Tase $ _2 $。 $^{77} $ se光谱的温度依赖性在PD插入时出乎意料的线变窄，揭开了相关的局部晶格扭曲的存在，远远高于电荷密度波（CDW）顺序的过渡温度，从而支持2H-TASE $ _2 $ _2 $ _2 $ _2 $ _2 $ _2 $ _2 $ _2 $中的CDW机制。同时，骑士移位数据表明，不稳定的CDW过渡涉及部分费米表面间隙的开口。至于自旋动力学，$^{77} $ se旋转晶格放松率$ t_1^{ - 1} $作为温度的函数表明，伪甘油行为甚至在CDW阶段甚至在CDW阶段中占主导地位，并且在PD-6％样本中也变得更强大，并且在PD-6％样本中变得更强大。我们讨论CDW波动可能导致伪群和超导性，尽管这两种现象不太可能直接相互联系。
Single crystals of pristine and 6% Pd-intercalated 2H-TaSe$_2$ have been studied by means of $^{77}$Se nuclear magnetic resonance (NMR). The temperature dependence of the $^{77}$Se spectrum, with an unexpected line narrowing upon Pd intercalation, unravels the presence of correlated local lattice distortions far above the transition temperature of the charge density wave (CDW) order, thereby supporting a strong-coupling CDW mechanism in 2H-TaSe$_2$. While, the Knight shift data suggest that the incommensurate CDW transition involves a partial Fermi surface gap opening. As for spin dynamics, the $^{77}$Se spin-lattice relaxation rate $T_1^{-1}$ as a function of temperature shows that a pseudogap behavior dominates the low-energy spin excitations even within the CDW phase, and gets stronger along with superconductivity in the Pd-6% sample. We discuss that CDW fluctuations may be responsible for the pseudogap as well as superconductivity, although the two phenomena are unlikely to be directly linked each other.
