Evidence for anisotropic excitonlike enhancement of the Raman scattering from La/sub 2/CuO/sub 4/

Journal Article · Fri Jul 01 04:00:00 EDT 1988 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.38.917· OSTI ID:7202798

Weber, W H; Peters, C R; Wanklyn, B M; Chen, C; Watts, B E

Polarized Raman studies on oriented single crystals of La/sub 2/CuO/sub 4/ yield ..cap alpha../sub z//sub z/ spectra with narrow lines at 429 and 228 cm/sup -1/ that are identified as the two A/sub 1//sub g/ modes expected for the tetragonal K/sub 2/NiF/sub 4/ structure; ..cap alpha../sub x//sub z/ spectra with one line at 228 cm/sup -1/ that has E/sub g/ symmetry; and ..cap alpha../sub x//sub x/ spectra with numerous peaks that are due to normally forbidden phonon excitations. The ..cap alpha../sub x//sub x/ spectra also show strong second-order features, suggesting a highly anisotropic, excitonlike enhancement of the Raman scattering.

• Research Organization: Research Staff, Ford Motor Company, Dearborn, Michigan 48121
• OSTI ID: 7202798
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 38:1; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ANISOTROPY
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTALS
LANTHANUM COMPOUNDS
LANTHANUM OXIDES
MONOCRYSTALS
OXIDES
OXYGEN COMPOUNDS
PHONONS
POLARIZATION
QUASI PARTICLES
RAMAN SPECTRA
RARE EARTH COMPOUNDS
SPECTRA
TETRAGONAL LATTICES
TRANSITION ELEMENT COMPOUNDS