skip to main content

SciTech ConnectSciTech Connect

Title: Nanoscale mechanical switching of ferroelectric polarization via flexoelectricity

Flexoelectric coefficient is a fourth-rank tensor arising from the coupling between strain gradient and electric polarization and thus exists in all crystals. It is generally ignored for macroscopic crystals due to its small magnitude. However, at the nanoscale, flexoelectric contributions may become significant and can potentially be utilized for device applications. Using the phase-field method, we study the mechanical switching of electric polarization in ferroelectric thin films by a strain gradient created via an atomic force microscope tip. Our simulation results show good agreement with existing experimental observations. We examine the competition between the piezoelectric and flexoelectric effects and provide an understanding of the role of flexoelectricity in the polarization switching. Also, by changing the pressure and film thickness, we reveal that the flexoelectric field at the film bottom can be used as a criterion to determine whether domain switching may happen under a mechanical force.
Authors:
; ; ;  [1]
  1. Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
Publication Date:
OSTI Identifier:
22399120
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 2; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ATOMIC FORCE MICROSCOPY; COMPUTERIZED SIMULATION; COUPLING; CRYSTALS; FERROELECTRIC MATERIALS; NANOSTRUCTURES; PIEZOELECTRICITY; POLARIZATION; POTENTIALS; STRAINS; TENSORS; THIN FILMS