有机铁电共聚物P(VDF-TrFE)铁电极化反转机理的STM研究

The study of mechanism of polarization reversal in ferroelectric copolymer P(VDF TrFE)

本文用一种改装了的ＳＴＭ技术，可以直接观察到聚偏氟乙烯（ＰＶＤＦ）的共聚物Ｐ（ＶＤＦ－ＴｒＦＥ）的铁电畴。这一技术我们称之为“局域压电性”探测技术。通过测量有机铁电共聚物Ｐ（ＶＤＦ－ＴｒＦＥ）样品的表面振动，我们可以清楚地分辨出正、负和非振动畴，并记录下极化反转过程中畴结构的变化。实验结果可以用一个“非平衡的四阱势”

Using a modified scanning tunneling microscope,we developed a ‘local piezoelectric’ detecting technique for investigating the organic piezoelectric phenomena in ferroelectric copolymer P(VDF TrFE). By measuring the surface vibration of the copolymer sample, we were able to sharply distinguish the positive,negative and nonvibration domains, and monitor the variation of the domain structure during a polarization reversal process. Our observation can be explained by a “non equivalent 4 site” model.