Gradual disappearance of the Fermi surface near the metal-insulator transition in La 1 − x Sr x Mn O 3 thin films
Gradual disappearance of the Fermi surface near the metal-insulator transition in La 1 − x Sr x Mn O 3 thin films
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DOI：
10.1103/physrevb.76.201103
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发表时间：
2007-05
影响因子：
3.7
通讯作者：
A. Chikamatsu;H. Wadati;H. Kumigashira;M. Oshima;A. Fujimori;M. Lippmaa;K. Ono;M. Kawasaki;H. Koinuma
中科院分区：
文献类型：
--
作者：
A. Chikamatsu;H. Wadati;H. Kumigashira;M. Oshima;A. Fujimori;M. Lippmaa;K. Ono;M. Kawasaki;H. Koinuma
本文报道了用外延薄膜的原位角度分辨光电子能谱观察${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}\mathrm{Mn}{\mathrm{O}}_{3}$(LSMO)在填充控制金属-绝缘体(MI)转变过程中电子结构的变化。通过将光谱权重从费米能级附近的相干带转移到低Hubbard带，费米面在MI跃迁附近逐渐消失，而金属LSMO在{E}F}附近的ARPES谱中也存在伪隙行为。这些结果表明，由强电子-电子相互作用引起的光谱重量转移主导了填充-控制MI跃迁所引起的LSMO中的能隙形成。
We report the observation of changes in the electronic structure of ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}\mathrm{Mn}{\mathrm{O}}_{3}$ (LSMO) across the filling-control metal-insulator (MI) transition by means of in situ angle-resolved photoemission spectroscopy (ARPES) of epitaxial thin films. The Fermi surface gradually disappears near the MI transition by transferring spectral weight from the coherent band near the Fermi level $({E}_{F})$ to the lower Hubbard band, whereas a pseudogap behavior also exists in the ARPES spectra in the close vicinity of ${E}_{F}$ for metallic LSMO. These results indicate that the spectral weight transfer derived from strong electron-electron interaction dominates the gap formation in LSMO associated with the filling-control MI transition.