In situ photoemission study on atomically-controlled La$_{1-x}$Sr$_x$MnO$_3$ thin films: Composition dependence of the electronic structure

K. Horiba; A. Chikamatsu; H. Kumigashira; M. Oshima; N. Nakagawa; M. Lippmaa; K. Ono; M. Kawasaki; H. Koinuma

doi:10.1103/PhysRevB.71.155420

paper

In situ photoemission study on atomically-controlled La $_{1 - x}$ Sr $_{x}$ MnO $_{3}$ thin films: Composition dependence of the electronic structure

arXiv:cond-mat/0406315 · doi:10.1103/PhysRevB.71.155420

Abstract

We have investigated change in the electronic structures of atomically-controlled La $_{1 - x}$ Sr $_{x}$ MnO $_{3}$ (LSMO) thin films as a function of hole-doping level ( $x$ ) in terms of {\it in situ} photoemission spectroscopy (PES) and x-ray absorption spectroscopy (XAS) measurements. The {\it in situ} PES measurements on a well-ordered surface of high-quality epitaxial LSMO thin films enable us to reveal their intrinsic electronic structures, especially the structure near the Fermi level ( $E_{F}$ ). We have found that overall features of valence band as well as the core levels monotonically shifted toward lower binding energy as $x$ was increased, indicating the rigid-band like behavior of underlying electronic structure of LSMO thin films. The peak nearest to $E_{F}$ due to the $e_{g}$ orbital is also found to move toward $E_{F}$ in a rigid-band manner, while the peak intensity decreases with increasing $x$ . The loss of spectral weight with $x$ in the occupied density of states was compensated by simultaneous increment of the shoulder structure in O 1 $s$ XAS spectra, suggesting the existence of a pseudogap, that is depression in spectral weight at $E_{F}$ , for all metallic compositions. These results indicate that the simple rigid-band model does not describe the electronic structure near $E_{F}$ of LSMO and that the spectral weight transfer from below to above $E_{F}$ across the gap dominates the spectral changes with $x$ in LSMO thin films.

8 pages, 8 figures

In situ photoemission study on atomically-controlled La $_{1 - x}$ Sr $_{x}$ MnO $_{3}$ thin films: Composition dependence of the electronic structure

Abstract

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In situ photoemission study on atomically-controlled La1−x​Srx​MnO3​ thin films: Composition dependence of the electronic structure

Abstract

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Cited by in corpus (20)

In situ photoemission study on atomically-controlled La $_{1 - x}$ Sr $_{x}$ MnO $_{3}$ thin films: Composition dependence of the electronic structure