TY - JOUR
T1 - Effects of lanthanum dopants on the Curie-Weiss and the local order behaviors for Pb1-xLax(Fe2/3W 1/3)0.7Ti0.3O3 relaxor ferroelectrics
AU - Hong, Cheng Shong
AU - Chu, Sheng Yuan
AU - Tsai, Cheng Che
AU - Hsu, Chi Cheng
AU - Su, Hsiu Hsien
N1 - Funding Information:
This research was supported by the National Science Council of Republic of China , under grant NSC-99-2221-E-017-005 .
PY - 2013/2
Y1 - 2013/2
N2 - The effects of lanthanum dopants are investigated on the dielectric responses for Pb1-xLax(Fe2/3W 1/3)0.7Ti0.3O3 ceramics. According to the experimental data and fitting results, it is concluded that the dielectric characteristics are changed from a long-range-ordered (LRO) ferroelectric state to a short-range-ordered (SRO) relaxor by increasing the amounts of lanthanum dopants. Furthermore, the spin glassy behaviors and the freezing process of local polarizations are not only affected by the ordering degree of B-site cations but also affected by the defect polar pairs. Their response mechanisms are proposed that the growth of the 1:1 ordered domain Pb1-xLax(Fe1/2W1/2)O3 is impeded since its charge imbalance is enhanced by increasing the amounts of lanthanum dopants, and the defect polar pairs of lead, tungsten and oxygen vacancy are induced by the pyrochlore phase, PbWO4 or Pb 0.99La0.01WO4, when the amount of lanthanum dopants exceed 5 mol.%.
AB - The effects of lanthanum dopants are investigated on the dielectric responses for Pb1-xLax(Fe2/3W 1/3)0.7Ti0.3O3 ceramics. According to the experimental data and fitting results, it is concluded that the dielectric characteristics are changed from a long-range-ordered (LRO) ferroelectric state to a short-range-ordered (SRO) relaxor by increasing the amounts of lanthanum dopants. Furthermore, the spin glassy behaviors and the freezing process of local polarizations are not only affected by the ordering degree of B-site cations but also affected by the defect polar pairs. Their response mechanisms are proposed that the growth of the 1:1 ordered domain Pb1-xLax(Fe1/2W1/2)O3 is impeded since its charge imbalance is enhanced by increasing the amounts of lanthanum dopants, and the defect polar pairs of lead, tungsten and oxygen vacancy are induced by the pyrochlore phase, PbWO4 or Pb 0.99La0.01WO4, when the amount of lanthanum dopants exceed 5 mol.%.
UR - http://www.scopus.com/inward/record.url?scp=84871720840&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84871720840&partnerID=8YFLogxK
U2 - 10.1016/j.materresbull.2012.09.053
DO - 10.1016/j.materresbull.2012.09.053
M3 - Article
AN - SCOPUS:84871720840
SN - 0025-5408
VL - 48
SP - 200
EP - 206
JO - Materials Research Bulletin
JF - Materials Research Bulletin
IS - 2
ER -