Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska-Lincoln, Nebraska 68588-0299, United States.
Nano Lett. 2011 May 11;11(5):1970-5. doi: 10.1021/nl200221z. Epub 2011 Apr 4.
We have demonstrated an effective electrical control of polarization in the individual crystalline nanomesas of the ferroelectric polymer, poly(vinylidene fluoride)-trifluoroethylene (PVDF-TrFE) and its relation to the polymer structure. The mechanism of polarization reversal has been investigated via sub-10 nm real space imaging of domain pattern evolution under an applied electric field. The domain switching behavior revealed in PVDF-TrFE nanomesas is drastically different from that observed in inorganic solid-state crystalline ferroelectrics. The nanoscale features of the switching process include remote domain nucleation and spatially nonuniform wall velocity. Local switching spectroscopy and domain dynamics studies relate the observed switching features to a random-bond type disorder associated with defects in conformation and molecular packing.
我们已经证明了在铁电聚合物聚（偏二氟乙烯-三氟乙烯）（PVDF-TrFE）及其与聚合物结构的单个晶状纳米盘中，极化可以得到有效的电控。通过在施加电场下对畴图案演化进行亚 10nm 实空间成像，研究了反转极化的机制。在 PVDF-TrFE 纳米盘中观察到的畴开关行为与无机固态晶态铁电体中的行为有很大的不同。开关过程的纳米级特征包括远程畴成核和空间不均匀的壁速度。局部开关光谱和畴动力学研究将观察到的开关特征与与构象和分子堆积缺陷相关的随机键型无序联系起来。
