Strain, temperature, and electric-field effects on the phase transition and piezoelectric responses of K0.5Na0.5NbO3 thin films
Abstract
A KNbO3-based solid solution system is environmentally friendly with good electromechanical performance. This work established the misfit strain–strain and temperature–strain phase diagrams for K0.5Na0.5NbO3 thin films and calculated the polarization switching, phase transition, and piezoelectric responses of K0.5Na0.5NbO3 thin films under various strains, temperatures, and electric fields. The results show that the piezoelectric coefficient d33 can be enhanced near the phase boundaries. For the ferroelectric phase with a nonzero out-of-plane polarization component, an optimal electric field is identified for maximizing d33, which is desired in applications such as thin-film piezoelectric micro-electromechanical systems, transducers for ultrasound medical imaging, and energy harvesting. The present results are expected to provide guidance for the future experimental study of KxNa1−xNbO3 thin films and the optimization of ferroelectric thin film-based devices.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 20, 2018
- Source ID
- 10.1063/1.5027505
Entities
People
- Ce-wen Nan
- Jian-Jun Wang
- Long-Qing Chen
- Meng-jun Zhou
Organizations
- Air Force Office of Scientific Research
- China Scholarship Council
- National Natural Science Foundation of China
- Pennsylvania State University
- Tsinghua University