Direct evidence of an incommensurate phase in NaNbO{sub 3} and its implication in NaNbO{sub 3}-based lead-free antiferroelectrics

Journal Article · Mon Sep 14 04:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4930067· OSTI ID:22482091

Guo, Hanzheng; Shimizu, Hiroyuki ^[1]

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1. Taiyo Yuden Co., Ltd., Takasaki, Gunma 370-3347 (Japan)

Hot-stage in situ transmission electron microscopy was employed to investigate the temperature-induced complex sequence of phase transitions in NaNbO{sub 3} polycrystalline. In addition to the commonly recognized P (Pbma) → R (Pmnm) → S (Pnmm) phase transitions, incommensurate phases were observed to exist in P and R phase regions. The former (in the P → R transition region) is coincident with a diffused dielectric peak appearing at ∼170 °C, and the latter (in the R → S transition region) serves as an intermediate structure to bridge the two sub-phases in the R phase region. The incommensurate phase in the P phase region can be inferred from the polarization current density and differential dielectric permittivity anomalies, and it provides the bridge structure during the electric field-induced polarization reversal and antiferroelectric-to-ferroelectric transition in NaNbO{sub 3} solid solutions.

• OSTI ID: 22482091
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 11 Vol. 107; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CURRENT DENSITY
ELECTRIC FIELDS
FERROELECTRIC MATERIALS
INTERMEDIATE STRUCTURE
PEAKS
PERMITTIVITY
PHASE TRANSFORMATIONS
POLARIZATION
POLYCRYSTALS
SOLID SOLUTIONS
TRANSMISSION ELECTRON MICROSCOPY