Optical spectroscopy of the charge-ordering transition in La{sub 1.67}Sr{sub 0.33}NiO{sub 4}

Journal Article · Fri Nov 01 04:00:00 EST 1996 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.54.R14230· OSTI ID:397581

Katsufuji, T; Tanabe, T; Ishikawa, T; Fukuda, Y; Arima, T; Tokura, Y ^[1]

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1. Department of Applied Physics, University of Tokyo, Tokyo 113 (Japan)

Optical spectra of a single crystal of La{sub 1.67}Sr{sub 0.33}NiO{sub 4}, which undergoes a charge-ordering transition at {ital T}{sub CO}{approximately}240 K, have been investigated for wide ranges of photon energy (0.008{endash}3 eV) and temperature (10{endash}480 K). The opening of a charge gap as well as change of the gap magnitude (2{Delta}) with temperature is clearly observed below {ital T}{sub CO}, with an anomalously large ratio of 2{Delta}({ital T}=0)/{ital k}{sub {ital B}}{ital T}{sub CO} ({approximately}13). Conspicuous spectral change with temperature is also observed above {ital T}{sub CO} over the energy region up to 2 eV, which suggests persistent fluctuation of the charge ordering or formation of small polarons above {ital T}{sub CO}. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 397581
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 20 Vol. 54; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ELECTRIC CONDUCTIVITY
ENERGY GAP
INFRARED SPECTRA
LANTHANUM OXIDES
NICKEL OXIDES
OPTICAL PROPERTIES
PHASE TRANSFORMATIONS
PHONONS
POLARONS
STRONTIUM OXIDES
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0-13 K
TEMPERATURE RANGE 1000-4000 K
TEMPERATURE RANGE 273-400 K
TEMPERATURE RANGE 400-1000 K
TEMPERATURE RANGE 65-273 K
ULTRAVIOLET SPECTRA
VISIBLE SPECTRA