Resonant-photoemission study of Nd sub 2 minus x Ce sub x CuO sub 4

Journal Article · Sun Apr 01 00:00:00 EST 1990 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.41.7205· OSTI ID:7122724

Namatame, H; Fujimori, A; Tokura, Y ^[1]; Nakamura, M; Yamaguchi, K; Misu, A ^[2]; Matsubara, H; Suga, S ^[3]; Eisaki, H; Ito, T; Takagi, H; Uchida, S ^[4]

---

1. Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan (JP)
2. Department of Physics, Science University of Tokyo, Kagurazaka, Shinjuku-ku, Tokyo 162, Japan (JP)
3. Synchrotron Radiation Laboratory, Institute for Solid State Physics, University of Tokyo, Tanashi, Tokyo 188, Japan (JP)
4. Engineering Research Institute, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan (JP)

We have studied the photoemission spectra of Nd{sub 2{minus}{ital x}}Ce{sub {ital x}}CuO{sub 4} (0.05{le}{ital x}{le}0.2) using synchrotron radiation in the Cu 3{ital p}{r arrow}3{ital d}, Nd 4{ital d}{r arrow}4{ital f}, and Ce 4{ital d}{r arrow}4{ital f} core absorption regions. The valence-band satellite corresponding to Cu{sup 2+} shows a resonance behavior. The Nd 4{ital f}--derived photoemission spectrum shows a double-peak structure, which is characteristic of the localized 4{ital f}{sup 3} ground state and strong 4{ital f}--O 2p hybridization. The Ce 4{ital f}--derived photoemission is distributed predominantly near the top of the O 2{ital p} band. Comparing the results with those of La{sub 2{minus}{ital x}}Sr{sub {ital x}}CuO{sub 4}, we find that the Fermi level is located only {approx}0.7 eV above the top of the valence band in spite of the large (1.5--eV) band gap of Nd{sub 2}CuO{sub 4}, indicating that the Fermi level of Nd{sub 2{minus}{ital x}}Ce{sub {ital x}}CuO{sub 4} lies within the band gap of Nd{sub 2}CuO{sub 4}.

• OSTI ID: 7122724
• Journal Information: Physical Review, B: Condensed Matter; (USA), Vol. 41:10; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CERIUM OXIDES
ELECTRONIC STRUCTURE
COPPER OXIDES
NEODYMIUM OXIDES
ENERGY SPECTRA
FERMI LEVEL
HYBRIDIZATION
PHOTOEMISSION
SUPERCONDUCTORS
SYNCHROTRON RADIATION
BREMSSTRAHLUNG
CERIUM COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
ELECTROMAGNETIC RADIATION
EMISSION
ENERGY LEVELS
NEODYMIUM COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
RADIATIONS
RARE EARTH COMPOUNDS
SECONDARY EMISSION
SPECTRA
TRANSITION ELEMENT COMPOUNDS
360204* - Ceramics
Cermets
& Refractories- Physical Properties