Web of Science: 23 citations, Scopus: 23 citations, Google Scholar: citations,
Nanomechanics of flexoelectric switching
Očenášek, Jan (University of West Bohemia in Pilsen)
Lu, Haidong (University of Nebraska-Lincoln. Department of Physics and Astronomy)
Bark, C.W. (University of Wisconsin-Madison. Department of Materials Science and Engineering)
Eom, C.B. (University of Wisconsin-Madison. Department of Materials Science and Engineering)
Alcalá, Jorge (Universitat Politècnica de Catalunya. Departament de Ciència dels Materials i Enginyeria Metal·lúrgica)
Catalan, Gustau (Institut Català de Nanociència i Nanotecnologia)
Gruverman, A. (University of Nebraska-Lincoln. Department of Physics and Astronomy)

Date: 2015
Abstract: We examine the phenomenon of flexoelectric switching of polarization in ultrathin films of barium titanate induced by a tip of an atomic force microscope (AFM). The spatial distribution of the tip-induced flexoelectricity is computationally modeled both for perpendicular mechanical load (point measurements) and for sliding load (scanning measurements), and compared with experiments. We find that (i) perpendicular load does not lead to stable ferroelectric switching in contrast to the load applied in the sliding contact load regime, due to nontrivial differences between the strain distributions in both regimes: ferroelectric switching for the perpendicular load mode is impaired by a strain gradient inversion layer immediately underneath the AFM tip; while for the sliding load regime, domain inversion is unimpaired within a greater material volume subjected to larger values of the mechanically induced electric field that includes the region behind the sliding tip; (ii) beyond a relatively small value of an applied force, increasing mechanical pressure does not increase the flexoelectric field inside the film, but results instead in a growing volume of the region subjected to such field that aids domain nucleation processes; and (iii) the flexoelectric coefficients of the films are of the order of few nC/m, which is much smaller than for bulk BaTiO3 ceramics, indicating that there is a "flexoelectric size effect" that mirrors the ferroelectric one.
Note: Número d'acord de subvenció EC/FP7/308023
Note: Número d'acord de subvenció MINECO/FIS2013-48668-C2-1-P
Note: Número d'acord de subvenció MINECO/MAT2011-23375
Rights: Tots els drets reservats.
Language: Anglès.
Document: article ; recerca ; acceptedVersion
Published in: Physical Review B, Vol. 92, Issue 3 (July 2015) , art. 035417, ISSN 1550-235X

DOI: 10.1103/PhysRevB.92.035417


Postprint
23 p, 2.2 MB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (scientific output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles

 Record created 2019-06-03, last modified 2019-10-21



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