Fig. 4: Schematic, electric impedance and phase spectra of the 31–36 coupled mode OSSPSU stator.

a The stator schematic image. The red arrow shows the direction of poling. b The impedance and phase spectra of [001]-PIMNT crystal-OSSPSU stator. c The impedance and phase spectra of the hard ceramic-OSSPSU stators. The inset in b shows the schematic of vibration modes for 31 and 36 of the OSSPSU stators.