Mass renormalization in the bandwidth-controlled Mott-Hubbard systems SrVO 3 and CaVO 3 studied by angle-resolved photoemission spectroscopy
Mass renormalization in the bandwidth-controlled Mott-Hubbard systems SrVO 3 and CaVO 3 studied by angle-resolved photoemission spectroscopy
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DOI：
10.1103/physrevb.82.085119
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发表时间：
2010-03
影响因子：
3.7
通讯作者：
T. Yoshida;M. Hashimoto;T. Takizawa;A. Fujimori;M. Kubota;K. Ono;H. Eisaki
中科院分区：
文献类型：
--
作者：
T. Yoshida;M. Hashimoto;T. Takizawa;A. Fujimori;M. Kubota;K. Ono;H. Eisaki
${\text{Ca}}_{1\ensuremath{-}x}{\text{Sr}}_{x}{\text{VO}}_{3}$是一个mott - hubhard型相关电子系统，其带宽可以随V-O-V键角的变化而变化，但带宽控制对电子结构的实际影响在以往的光电实验中一直存在争议。本文用角分辨光谱学研究了${\text{SrVO}}_{3}$和${\text{CaVO}}_{3}$的带色散和费米面。在费米能级$({E}_{F})$附近，已经观察到三条由$\text{V}\text{3d$ ${t}_{2g}$轨道形成的圆柱形费米面。观察到的两种化合物的带宽几乎是局部密度近似带结构计算预测的一半，证实了电子相关引起的质量重整化。结果表明，${\text{CaVO}}_{3}$中的$d$带宽度比${\text{SrVO}}_{3}$中的窄，与带结构计算结果定性一致。讨论了正交晶格畸变和电子相关在观察到的能带变窄中的作用。
${\text{Ca}}_{1\ensuremath{-}x}{\text{Sr}}_{x}{\text{VO}}_{3}$ is a Mott-Hubbard-type correlated electron system whose bandwidth can be varied by the V-O-V bond angle but the actual effect of bandwidth control on the electronic structure has been controversial in previous photoemission experiments. In this work, band dispersions and Fermi surfaces of ${\text{SrVO}}_{3}$ and ${\text{CaVO}}_{3}$ are studied by angle-resolved photoemission spectroscopy. Near the Fermi level $({E}_{F})$, three bands forming cylindrical Fermi surfaces derived from the three $\text{V}\text{ }3d$ ${t}_{2g}$ orbitals have been observed. The observed bandwidths for both compounds are almost half of those predicted by local-density approximation band-structure calculation, confirming mass renormalization caused by electron correlation. It has been clearly demonstrated that the width of the $d$ band in ${\text{CaVO}}_{3}$ is narrower than that in ${\text{SrVO}}_{3}$, qualitatively consistent with the result of band-structure calculation. Roles of the orthorhombic lattice distortion and electron correlation in the observed band narrowing are discussed.