POLAR PHASE INSTABILITY IN THE PARAELECTRIC REGION OF PMN-PT RELAXOR FERROELECTRIC CRYSTALS
AbstractThe phase instabilities in the (1-x)Pb(Mg1/3Nb2/3)-xPbTiO3 (PMN-xPT) relaxor ferroelectric single crystals with orientations  and  were investigated as a function of temperature and dc-bias voltage. The composition of crystals was in the range of morphotropic phase boundary (MPB) region with x 0.33. Two structural phase transition anomalies were observed in the temperature dependent capacitance of the two crystals related to paraelectric cubic to ferroelectric tetragonal and then to rhombohedral/monoclinic symmetry changes. A remarkable shift in the cubic-tetragonal phase transition boundary towards the higher temperature side was observed with increasing bias voltage. The origin of this dc-bias assisted unusual instability, apparently inside the cubic phase, was associated to the presence and complex dynamics of polar nanoregions (PNRs).
S.-E. Park and T.R. Shrout, J. Appl. Phys. 82
J. Kuwata, K. Uchino and S. Nomura, Jpn. J. Appl.
Phys. 21 (1982) 1298.
G. Burns and B.A. Scott, Solid State Commun. 13
W. Dmowski, S.B. Vakhrushev, I.-K. Jeong, M.P.
Hehlen, F. Trouw and T. Egami, Phys. Rev. Lett.
V. Bobnar and Z. Kutnjak, Ferroelectrics 415
D. Viehland, J.F. Li and A. Amin, J. Appl. Phys. 92
G. Shabbir, S. Kojima and C. Feng, J. Appl. Phys.
D. Lin, Z. Li, S. Zhang, Z. Xu and X. Yao, J. Appl.
Phys. 108 (2010) 034112.
S.G. Lushnikov, J.-H. Ko and S. Kojima, Appl.
Phys. Lett. 84 (2004) 4798.
E. Dulkin, M. Roth, B. Dkhil and J.M. Kiat, J.
Appl. Phys. 98 (2005) 023520.
M. Iwata, K. Tanaka, M. Maeda and Y. Ishibashi,
Ferroelectrics 440 (2012) 67.
Z.R. Li, Z.Z. Xi, Z. Xu and X. Yao, J. Mater. Sci.
Lett. 21 (2002) 1325.
G. Shabbir, C. Feng and S. Kojima, Trans. Mat.
Res. Soc. Jpn. 29 (2004) 1131.
H. Cao, C. Stock, G. Xu, P.M. Gehring, J. Li and D.
Viehland, Phys. Rev. B 78 (2008) 104103.