Temperature dependent near infrared ultraviolet range dielectric functions of nanocrystalline (Na{sub 0.5}Bi{sub 0.5}){sub 1−x}Ce{sub x}(Ti{sub 0.99}Fe{sub 0.01})O{sub 3} films

Journal Article · Mon Jan 27 00:00:00 EST 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4863417· OSTI ID:22280555

Zhang, S.; Zhang, J. Z.; Han, M. J.; Li, Y. W.; Chu, J. H. ^[1]

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1. Key Laboratory of Polar Materials and Devices, Ministry of Education, Department of Electronic Engineering, East China Normal University, Shanghai 200241 (China)

Optical properties and phase transition of Ce-modified (Na{sub 0.5}Bi{sub 0.5})(Ti{sub 0.99}Fe{sub 0.01})O{sub 3} nanocrystalline films have been investigated by spectroscopic ellipsometry from −70 to 500 °C. Temperature dependent dielectric functions in the photon energy range of 0.6–6.4 eV can be derived by the Tauc-Lorentz model. It was found that the features in dielectric function (ε) showed an abrupt variation near 200 and 340 °C, respectively. The phenomena can be explained by the appearance and/or reversal of polarization. It indicates that ferroelectric (rhombohedral) to paraelectric (tetragonal) phase transition is related to electronic band variation, which is observed by this technique.

• OSTI ID: 22280555
• Journal Information: Applied Physics Letters, Vol. 104, Issue 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
77 NANOSCIENCE AND NANOTECHNOLOGY
BISMUTH COMPOUNDS
CERIUM COMPOUNDS
CRYSTALS
ELLIPSOMETRY
EV RANGE
FERROELECTRIC MATERIALS
IRON COMPOUNDS
NANOSTRUCTURES
OPTICAL PROPERTIES
PERMITTIVITY
PHASE TRANSFORMATIONS
POLARIZATION
SODIUM COMPOUNDS
TEMPERATURE DEPENDENCE
TETRAGONAL LATTICES
THIN FILMS
TITANATES
TRIGONAL LATTICES
ULTRAVIOLET RADIATION
VARIATIONS