论文标题
三元palladates的电子结构和孔掺杂的效果：价带光发射光谱研究
Electronic structure of ternary palladates and effect of hole doping: A valence band photoemission spectroscopic study
论文作者
论文摘要
我们使用Valence Band光学光谱和频段结构计算研究了三元paldates $ a $ _3 $ o $ _4 $（$ a $ = sr，CA）的电子结构。实验价带光谱中价带的总宽度和各种特征的能量位置，通过使用混合功能的频带结构计算很好地捕获。 Band structure calculations within local density approximations lead to metallic ground state while the calculations using hybrid functional provide band gap of 0.25 eV and 0.22 eV for CaPd$_3$O$_4$ and SrPd$_3$O$_4$ respectively, suggesting moderated to strong electron correlation strength in these narrow band gap semiconducting palladates.高分辨率光谱揭示了母体化合物在费米水平上的强度忽略不计，而孔掺杂的srpd $ _3 $ o $ _4 $（在SR站点的15 \％li替代）表现出FERMI截止值，表明金属特征与半导体运输相反。这些观察结果揭示了在费米边缘落在迁移率边缘的情况下，电子定位的重要性。
We investigate the electronic structure of ternary palladates $A$Pd$_3$O$_4$ ($A$ = Sr, Ca) using valence band photoemission spectroscopy and band structure calculations. Overall width of the valence band and energy positions of various features in experimental valence band spectra are well captured by band structure calculations using hybrid functional. Band structure calculations within local density approximations lead to metallic ground state while the calculations using hybrid functional provide band gap of 0.25 eV and 0.22 eV for CaPd$_3$O$_4$ and SrPd$_3$O$_4$ respectively, suggesting moderated to strong electron correlation strength in these narrow band gap semiconducting palladates. High resolution spectra reveals negligibly small intensity at Fermi level for parent compounds while hole doped SrPd$_3$O$_4$ (by 15\% Li substitution at Sr site) exhibits a Fermi cut-off suggesting metallic character in contrast to semiconducting transport. These observations reveal the importance of localization of electrons in case where the Fermi edge falls in the mobility edge.
