论文标题
巨大的热电材料k $ _ {0.65} $ rho $ _2 $ _2美元
Anomalous band renormalization due to high energy $kink$ in the colossal thermoelectric material K$_{0.65}$RhO$_2$
论文作者
论文摘要
我们报告了使用高分辨率角度分辨光发射光谱（ARPES）技术和密度功能理论（DFT）计算进行研究的K $ _ {0.65} $ rho $ _2 $的低能电子结构和电子相关性。我们在费米表面上观察到一个高度相关的孔口袋。我们进一步注意到相关性取决于动量。最重要的是，在费米级附近的频段分散体中观察到了75 MeV和195 MeV的两个$ kinks $。虽然可以理解低能$ kink $是由于电子 - 波相互作用而被理解的，但在195 meV处的高能$扭结$的存在完全是该系统的新发现，导致频段恢复反应。基于对我们的实验数据的系统分析，我们提出高频授权激发作为高能量异常的合理起源。此外，我们注意到，高能量异常在获得K $ _ {0.65} $ RHO $ _2 $的巨大热电功率方面具有重要意义。
We report on low-energy electronic structure and electronic correlations of K$_{0.65}$RhO$_2$, studied using high-resolution angle-resolved photoemission spectroscopy (ARPES) technique and density functional theory (DFT) calculations. We observe a highly correlated hole pocket on the Fermi surface. We further notice that the correlations are momentum dependent. Most importantly, two $kinks$ at binding energies of 75 meV and 195 meV have been observed from the band dispersion in the vicinity of the Fermi level. While the low energy $kink$ at 75 meV can be understood as a result of the electron-phonon interaction, the presence of high energy $kink$ at 195 meV is totally a new discovery of this system leading to an anomalous band renormalization. Based on systematic analysis of our experimental data, we propose high frequency bosonic excitations as a plausible origin of the high energy anomaly. Further, we notice that the high energy anomaly has important implications in obtaining the colossal thermoelectric power of K$_{0.65}$RhO$_2$.
