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The continuous downscaling of microelectronic circuits combined with increasing interest in ferroelectric thin films for non-volatile random access memories (FeRAM) is drawing great attention to small ferroelectric thin film structures. There are various c ...
Relaxor-ferroelectric single crystals PZN-xPT [(1-x)Pb(Zn1/3Nb2/3)O3-xPbTiO3] and PMN-xPT [(1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3] continue to attract much interest due to their anomalously large piezoelectric properties (d33 > 2000 pm/V; k33 > 90%) when poled ("do ...
The transverse piezoelectric coefficient (d(31)(star)) has been calculated for tetragonal barium titanate (BT) and lead titanate (PT) cut along nonpolar axes, over a range of temperatures, using the phenomenological Landau-Ginzburg-Devonshire theory. It is ...
The mechanism of the giant unipolar strain recently observed in a lead-free piezoceramic, 0.92(Bi0.5Na0.5)TiO3-0.06BaTiO(3)-0.02(K0.5Na0.5)NbO3 [S.-T. Zhang, A. B. Kounga, E. Aulbach, H. Ehrenberg, and J. Rodel, Appl. Phys. Lett. 91, 112906 (2007) was inve ...
Electric-field-induced phase transitions have been evidenced by macroscopic strain measurements at temperatures between 25 degrees C and 100 degrees C in 001-poled (1-x)Pb(Mg1/3Nb2/3)O-3-xPbTiO(3) [(PMN-xPT);x=0.25,0.305,0.31] and (1-x)Pb(Zn1/3Nb2/3)O ...
Research on lead-free piezoceramics has dramatically increased over the last years due to stringent legislation demanding to phase out current lead- containing piezoceramics. The use of electrostrictive materials for electric-field induced strain has been ...
The present study aims at a better understanding of the high piezoelectric properties encountered in lead-based ferroelectrics by focusing on the extrinsic contributions to the response. The main characteristics of these materials are the highly nonlinear ...
The orientation dependence of the longitudinal piezoelectric coefficient, d(33)(*), is investigated as a function of temperature in BaTiO3 and PbTiO3 crystals using the Landau-Ginsburg-Devonshire theory. We show that a presence of the ferroelectric-ferroel ...
Systems with a ferroelectric to paraelectric transition in the vicinity of room temperature are useful for devices. Adjusting the ferroelectric transition temperature (T-c) is traditionally accomplished by chemical substitution - as in BaxSr1-xTiO3, the ma ...
This paper discusses the mechanisms that can contribute to the enhanced longitudinal piezoelectric effect along nonpolar directions in perovskite crystals, such as BaTiO3, PbTiO3, KNbO3, Pb(Mg1/3Nb2/3)O-3-PbTiO3 and Pb(Zn1/2Nb2/3)O-3-PbTiO3. Piezoelectric ...
