Researchers have developed polycrystalline lead zirconate titanium (PZT) ceramics that are actively maintained at the quadruple phase point (QP) using a temperature and electric field control module. This ceramic achieves a piezoelectric coefficient d33 of approximately 6850 pC/N, which is 10 to 30 times higher than commercial PZT ceramics and 4 times higher than commercial lead magnesium niotate-lead titanium single crystals. Performance remains stable at ambient temperatures from 25°C to 350°C. This property arises from the tricritical nature of the QP point, which creates an ultra-soft lattice and allows full polarization alignment in the polycrystals. The study overcomes a long-standing barrier in piezoelectric materials, where traditional PZT ceramics had d33 in the range of 200–600 pC/N and relaxor single crystals around 2000 pC/N. The research was published by a team led by Xiaobing Ren in the journal Science.[1][2]