Evidence for O{sub 2p} Hole-Driven Conductivity in La{sub 1{minus}x}Sr{sub x}MnO{sub 3} (0 {le} x {le} 0.7) and La{sub 0.7}Sr{sub 0.3}MnO{sub z} thin films

Journal Article · Mon Dec 02 04:00:00 EST 1996 · Physical Review Letters

OSTI ID:773628

Ju, H L ^[1]; Sohn, H C; Krishnan, K M

---

1. LBNL Library

Oxygen K-edge electron-energy-loss spectra have been measured for La{sub 1{minus}x}Sr{sub x}MnO{sub 3} (0 {le} x {le} 0.7) and La{sub 0.7}Sr{sub 0.3}MnO{sub z} thin films as a function of x and z. The spectra show a prepeak at the Fermi level, corresponding to transitions to empty states in the O{sub 2p} band, at the threshold of the K edge around 529 eV. This prepeak systematically increases with an increase in conductivity through divalent doping (x) or oxygen content (z). This confirms that these materials are charge-transfer-type oxides with carriers having significant oxygen 2p hole character. We argue that, the double exchange mechanism has to include the role of oxygen hole density to satisfactorily describe their transport properties.

• Research Organization: Lawrence Berkeley National Lab., CA (US)
• Sponsoring Organization: USDOE Director, Office of Science (US)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 773628
• Report Number(s): LBNL--39667
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 17 Vol. 79; ISSN 0031-9007; ISSN PRLTAO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ENERGY-LEVEL TRANSITIONS
ENERGY-LOSS SPECTROSCOPY
FERMI LEVEL
LANTHANUM OXIDES
MANGANESE OXIDES
OXYGEN
SPECTRA
STRONTIUM OXIDES
THIN FILMS