Abstract:
  Since 1997, Relaxor-PT solid solution single crystals have been the center focus in the field of ferroelectric materials. The giant piezoelectric effect of these single crystals has triggered a revolution in medical ultrasound. One interesting topic emerged from the study of these multidomain single crystals is domain pattern symmetry. Ferroelectric domains are no longer randomly distributed as in ferroelectric ceramics, but form a new category of domain pattern symmetries. Such macroscopic symmetries are regulated by the crystal symmetry and remaining domain variants after a designed poling process. One could manipulate these domain pattern symmetries to intentionally enhance a particular component of piezoelectric coefficient tensor and/or a particular functional property. This talk will analyze, from philosophical point of view, the correlation between microscopic symmetry and macroscopic domain pattern symmetry. The fundamental principle of functional property enhancement through domain engineering will also be discussed through particular examples.

CV：
曹文武教授于1982年初获吉林大学理论物理学士学位，1987年获美国宾夕法尼亚州立大学凝聚态物理博士学位。先后在宾州州立大学材料研究所和康奈尔大学原子和固体物理研究所做博士后， 1990年受聘为宾州州立大学教师，并最终于2001年获得数学系和材料研究院共聘的终身教授。 2006年被聘为教育部长江学者讲座教授，2009年入选中组部“千人计划”，2013年受聘科技部“973”计划首席科学家。