Frequency and Temperature Dependence of Dielectric Properties of Orthorhombic HoMnO₃ Thin Films

Abstract:

Orthorhombic HoMnO₃ films were prepared epitaxially on Nb-doped SrTiO₃ single crystal substrates by using pulsed laser deposition technique. The films showed perfectly a-axis crystallographic orientations. X-ray diffraction and atomic force microscopy were used to characterize the films. The complex dielectric properties were measured as functions of frequency (40 Hz~1 MHz) and temperature (80 K~300 K) with a signal amplitude of 50 mv. The respective dielectric relaxation peaks shifted to higher frequency as the measuring temperature increased, with the same development of real part of the complex permittivity. The cole-cole diagram was obtained according to the Debye model, and the effects of relaxation process were discussed.

• Periodical: Advanced Materials Research (Volumes 1025-1026)
• Pages: 427-431
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1025-1026.427
• Online since: September 2014
• Authors: Ping Gao, Wei Zhang, Wei Tian Wang*
• Keywords: Dielectric Property, HoMnO₃ Films, Loss Tangent, Orientation

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