Flexoelectric properties of ferroelectrics and the nanoindentation size-effect

M. Gharbi, Z. H. Sun, P. Sharma, K. White, Sami El-Borgi

Research output: Contribution to journalArticle

42 Citations (Scopus)

Abstract

Recent works have established the critical role of flexoelectricity in a variety of size-dependent physical phenomena related to ferroelectrics including giant piezoelectricity at the nanoscale, dead-layer effect in nanocapacitors, dielectric properties of nanostructures among others. Flexoelectricity couples strain gradients to polarization in both ordinary and piezoelectric dielectrics. Relatively few experimental works exist that have determined flexoelectric properties and they all generally involve some sort of bending tests on micro-specimens. In this work, we present a straightforward method based on nanoindentation that allows the evaluation of flexoelectric properties in a facile manner. The key contribution is the development of an analytical model that, in conjunction with indentation load-displacement data, allows an estimate of the flexoelectric constants. In particular, we confirm the experimental results of other groups on BaTiO3 which differ by three orders of magnitude from atomistic predictions. Our analytical model predicts (duly confirmed by our experiments) a strong indentation size-effect due to flexoelectricity.

Original languageEnglish
Pages (from-to)249-256
Number of pages8
JournalInternational Journal of Solids and Structures
Volume48
Issue number2
DOIs
Publication statusPublished - 15 Jan 2011
Externally publishedYes

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Keywords

  • Ferroelectrics
  • Flexoelectricity
  • Indentation

ASJC Scopus subject areas

  • Mechanical Engineering
  • Mechanics of Materials
  • Materials Science(all)
  • Condensed Matter Physics
  • Applied Mathematics
  • Modelling and Simulation

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