Phase Diagram of Sub‐GHz Electric‐Field‐Induced Polarization Oscillation

Abstract

Polarization oscillation under GHz electric field stimuli is a key issue for the future development of ultrafast sensor devices. An ultrafast phase‐field model is developed to study the phase diagram of polarization oscillation under sub‐GHz electric field for Pb(Zr,Ti)O3. At the morphotropic phase boundary region, the polarization and strain oscillation show maximum amplitude (electric field stimuli frequency <0.1 GHz). The phase difference of π/2 between the input of electric field and the polarization response, which can be tuned by the frequency of ac electric field stimuli, can lead to a maximum of polarization oscillation amplitude (electric field stimuli frequency >0.1 GHz). Moreover, under this phase difference, the polarization oscillation amplitude can be increased furthermore with the increasing ac electric field strength. With the absence of a phase transition, it is found that the polarization component along the z‐direction has a maximum oscillation amplitude of 0.2, and the strain has a maximum oscillation amplitude of 0.35%. The results provide useful guidance to explore and manipulate dynamic functionalities of ferroelectric sensing materials.