Dielectric and piezoelectric properties as a function of temperature for Pb(Yb/sub 1/2/Nb/sub 1/2/)O/sub 3/-PbTiO/sub 3/ single crystals

The dielectric and piezoelectric properties of high Curie temperature 0.6Pb(Yb/sub 1/2/Nb/sub 1/2/)O/sub 3/-0.4PbTiO/sub 3/ (PYNT40) single crystals as a function of temperature are reported. The Curie temperature of PYNT40 single crystals was about 270/spl deg/C and the rhombohedral to tetragonal phase transition temperature was /spl sim/168/spl deg/C. The piezoelectric and electromechanical coupling coefficients at room temperature were d/sub 33/ /spl sim/ 1200pC/N, k/sub 33/ /spl sim/ 88%, d /sub 31/ /spl sim/ -500 pC/N, k/sub 31/ /spl sim/ -76% and d/sub 15/ /spl sim/ 1700pC/N, k/sub 15/ /spl sim/ 88%, respectively. The coupling coefficients remained nearly constant until /spl sim/160/spl deg/C, indicating improved temperature stability compared to Pb(Zn/sub 1/3/Nb/sub 2/3/)O/sub 3/-PbTiO/sub 3/ and Pb(Mg/sub 1/3/Nb/sub 2/3/)O/sub 3/-PbTiO/sub 3/ single crystals.