Detection of phase transitions in sodium bismuth titanate-barium titanate single crystals by acoustic emission

Acoustic emission measurements are combined with strain, dielectric, and polarization measurements to detect phase transitions in 0.94 Na0.5 Bi0.5 Ti O3 -0.06BaTi O3 single crystals during thermal cycling as well as electric field cycling at both room temperature and 140 °C. All phase transitions known from the literature (cubictetragonaltrigonal Itrigonal II) are determined to be of first order, and the existence of the ferroelectric trigonal II phase at room temperature and its transformation into an antiferroelectric phase during heating above 130 °C is established.