Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/418
Title: Double hysteresis loop in Cu-doped K[sub 0.5]Na[sub 0.5]NbO₃ lead-free piezoelectric ceramics
Authors: Lin, D
Kwok, KW 
Chan, HLW 
Keywords: Potassium compounds
Sodium compounds
Copper compounds
Dielectric hys
Piezoceramics
Vacancies (crystal)
Dielectric polarisation
Solid-state phase transformations
Piezoelectricity
Issue Date: 4-Jun-2007
Publisher: American Institute of Physics
Source: Applied physics letters, 4 June 2007, v. 90, 232903, p. 1-3 How to cite?
Journal: Applied physics letters 
Abstract: In this letter the authors report the observation of double hysteresis loops in Cu-doped K[sub 0.5]Na[sub 0.5]NbO₃(KNN) ceramics. Unlike other ferroelectric titanates (e.g., BaTiO₃), aging is not required for the ceramic to exhibit the double-loop-like characteristics. Based on the symmetry-conforming principle of point defects, it is suggested that defect dipoles are formed by the acceptor dopant ions-Cu[sup 2+] and O²ˉ vacancies along the polarization direction after the diffuse tetragonal-orthorhombic phase transition of the ceramic. Because of the low migration rates of defects, the defect dipoles remain in the original orientation during the P-E loop measurement, providing a restoring force to reverse the switched polarization. The defect dipoles also provide “pinning” effects in the normal piezoelectric activities. As a result, the ceramic becomes “hardened,” exhibiting an extraordinarily high mechanical quality factor (2500), while the other piezoelectric properties remain reasonably good: electromechanical coupling coefficients k[sub p]=39%, k[sub t]=47%, and piezoelectric coefficient d[sub 33]=82 pC/N.
URI: http://hdl.handle.net/10397/418
ISSN: 0003-6951
DOI: 10.1063/1.2746087
Rights: © 2007 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in D. Lin & H.L.W. Chan, Appl. Phys. Lett. 90, 232903 (2007) and may be found at http://link.aip.org/link/?apl/90/232903
Appears in Collections:Journal/Magazine Article

Files in This Item:
File Description SizeFormat 
cu-doped_07.pdf477.04 kBAdobe PDFView/Open
Access
View full-text via PolyU eLinks SFX Query
Show full item record

SCOPUSTM   
Citations

86
Last Week
1
Last month
0
Citations as of Jun 3, 2016

WEB OF SCIENCETM
Citations

92
Last Week
1
Last month
0
Citations as of Sep 24, 2016

Page view(s)

721
Last Week
5
Last month
Checked on Sep 25, 2016

Download(s)

1,054
Checked on Sep 25, 2016

Google ScholarTM

Check

Altmetric



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.