Multi-type nanoscale domain switching dynamics in tetragonal PIN-PMN-PT single crystal under electrical bias

Domain switching coupled with polarization reorientation allows ferroelectrics to exhibit high potential for use in nonvolatile memories, electro-optic devices, and nanoelectronics. Although several studies have elucidated domain switching, the research on switching dynamics of complex nanoscale domain structures in relaxor-based ferroelectric materials has been lacking. Herein, the domain structure and domain switching dynamics in tetragonal PIMN-PT single crystals were systemically studied via piezoresponse force microscopy. An interlocking multi-type domain pattern comprising irregular 180° ferroelectric domains and regular 90° ferroelastic domains was observed and its formation mechanism was explored. Different domain switching dynamics of field-dependent responses were investigated. The results indicate that T-phase PIMN-PT single crystals exhibit a hierarchical domain switching process. Under a low electrical-bias stimuli (<10 V), the nucleation and growth of 180° domains dominate the switching process. By increasing the electrical bias from 10 V to 80 V, 90° domain switching was gradually completed and the sample achieved a single-domain state. The nucleation and growth mechanism of ferroelectric domains under electrical-bias stimuli were also discussed. Overall, our results deepened the understanding of ferroelectric switching in complex nanoscale domain structures and facilitate the use of precise domain tailoring technology for fabricating T-phase relaxor-based ferroelectric single crystals.