Zhou Zizhen, Yang Xiaolong, Wang Honghui, Han Guang, Lu Xu, Wang Guoyu, Wang Rui, Zhou Xiaoyuan
Center of Quantum Materials and Devices, College of Physics, Chongqing University, Chongqing 401331, China.
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China.
Fundam Res. 2022 Dec 30;5(1):145-150. doi: 10.1016/j.fmre.2022.12.012. eCollection 2025 Jan.
The band topology has been revealed to bring a wide array of novel electronic transport phenomena, but its interaction with phonon properties remains largely unexplored. Here we propose that continuous topological singularities with variable Fermi wave vectors can lead to giant effects on phonon transport in nodal-line semimetals. Using first-principles calculations, we show that such an exotic feature is present in a well-known topological semimetal ZrSiSe, in which the unique nodal-line can guarantee considerable momentum-continuous phonons to satisfy the stringent condition of Kohn anomaly and thereby dramatically strengthen the electron-phonon coupling. Moreover, the momentum-continuous anomaly phonons with eight arms of vertical Fermi surface drive intense phonon-electron scattering that is even comparable with intrinsic phonon-phonon scattering, giving rise to a reduction of ∼45% on room temperature lattice thermal conductivity. Our findings not only uncover giant phonon anomaly in topological nodal-line semimetals but also provide guidance for exploring the vital influence of electronic band topology on thermal transport bridged by the electron-phonon coupling.
能带拓扑已被证明会带来一系列新颖的电子输运现象，但其与声子特性的相互作用在很大程度上仍未得到探索。在此我们提出，具有可变费米波矢的连续拓扑奇点可导致节线半金属中声子输运的巨大效应。通过第一性原理计算，我们表明这种奇异特征存在于一种著名的拓扑半金属ZrSiSe中，其中独特的节线能够保证相当数量的动量连续声子满足科恩反常的严格条件，从而显著增强电子 - 声子耦合。此外，具有垂直费米面八条臂的动量连续反常声子驱动强烈的声子 - 电子散射，其甚至可与本征声子 - 声子散射相媲美，导致室温晶格热导率降低约45%。我们的发现不仅揭示了拓扑节线半金属中的巨大声子反常，还为探索电子能带拓扑通过电子 - 声子耦合对热输运的重要影响提供了指导。
