Raman investigation of the layered manganese perovskite La{sub 1.2}Sr{sub 1.8}Mn{sub 2}O{sub 7}
- National Inst. of Standards and Technology, Gaithersburg, MD (United States). Optical Technology Div.
- Argonne National Lab., IL (United States). Materials Science Div.
- Univ. of Maryland, College Park, MD (United States). Dept. of Physics
The authors report the results of a detailed polarization and temperature dependence study of the Raman scattering from La{sub 1.2}Sr{sub 1.8}Mn{sub 2}O{sub 7}. The Raman spectra reveal three general spectral features. First, there are sharp peaks due to long-wavelength optic phonons. Phonons, attributed to the distortion of the MnO{sub 6} octahedra, reveal an anomalous behavior which correlates with the transition from a paramagnetic-insulating (PI) to a ferromagnetic-metallic (FM) phase at a critical temperature {Tc}. Second, there is an electronic continuum that is suppressed for {omega} < 500 cm{sup {minus}1} at T {much_lt} {Tc}. Third, broad peaks between 400 cm{sup {minus}1} to 800 cm{sup {minus}1} seen in the PI state, surprisingly, disappear in the FM state. The implications of these results are discussed.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-31109-ENG-38
- OSTI ID:
- 323424
- Report Number(s):
- CONF-971201-; ISBN 1-55899-399-1; TRN: 99:004245
- Resource Relation:
- Conference: 1997 fall meeting of the Materials Research Society, Boston, MA (United States), 1-5 Dec 1997; Other Information: PBD: 1998; Related Information: Is Part Of Science and technology of magnetic oxides; Hundley, M.F. [ed.] [Los Alamos National Lab., NM (United States)]; Nickel, J.H. [ed.] [Hewlett-Packard Labs., Palo Alto, CA (United States)]; Ramesh, R. [ed.] [Univ. of Maryland, College Park, MA (United States)]; Tokura, Yoshinori [ed.] [Univ. of Tokyo (Japan)]; PB: 375 p.; Materials Research Society symposium proceedings, Volume 494
- Country of Publication:
- United States
- Language:
- English
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