论文标题
NMR对单组分分子导体中狄拉克节线的验证
NMR verification of Dirac nodal lines in a single-component molecular conductor
论文作者
论文摘要
Dirac Nodal线（DNL）是一种新型的无质量dirac费米子形式，沿着动量空间沿线存在。在这里，我们使用组合的NMR实验和数值模拟来验证分子材料中的真正DNL。 NMR光谱移位和自旋晶格松弛率除以温度，$ 1/t_1t $，分别与温度线性和四倍地降低，并在低温下变为恒定，与小费米口袋略微分散DNL一致。这些结果与DNL的模型模拟的比较揭示了费米速度的抑制和由于电子相关性引起的抗铁磁波动的增强以及Landau量化的影响。本研究提供了一个证明，以识别DNL并评估与NMR的相关效应。
The Dirac nodal line (DNL) is a novel form of massless Dirac fermions that reside along lines in momentum space. Here, we verify genuine DNLs in the molecular material, [Ni(dmdt)$_2$], with the combined NMR experiments and numerical simulations. The NMR spectral shift and spin-lattice relaxation rate divided by temperature, $1/T_1T$, decrease linearly and quadratically with temperature, respectively, and become constant at low temperatures, consistent with slightly dispersive DNLs with small Fermi pockets. Comparison of these results with model simulations of DNLs reveals the suppression of the Fermi velocity and the enhancement of antiferromagnetic fluctuations due to electron correlation as well as the influence of the Landau quantization. The present study offers a demonstration to identify the DNL and evaluate the correlation effect with NMR.
