Effect of disorder potential on domain switching behavior in polymer ferroelectric films
Effect of disorder potential on domain switching behavior in polymer ferroelectric films
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DOI：
10.1088/0957-4484/24/1/015706
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发表时间：
2013-01
期刊：
影响因子：
3.5
通讯作者：
P. Sharma;T. Nakajima;S. Okamura;A. Gruverman
中科院分区：
文献类型：
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作者：
P. Sharma;T. Nakajima;S. Okamura;A. Gruverman
使用共振增强压响应力显微镜，通过电致域结构演化的高分辨率实空间成像，研究了聚偏二氟乙烯-三氟乙烯（PVDF-TrFE 75/25）旋涂铁电共聚物薄膜中的纳米级开关动力学。已经表明，在强压印薄膜中，应用相反极性的切换脉冲会导致性质不同的域切换动态。域动力学的一个显着特征是在切换到优选偏振态期间域壁变得粗糙，而不是在切换到相反方向期间平滑域边界。观察到的开关行为可以通过空间均匀的内置电场和局部无序电位的综合效应来解释。外部电势的应用改变了两者之间的平衡，并创造了由平均内置电场或局部随机键无序电势主导域生长的条件。
Nanoscale switching dynamics in spin-coated ferroelectric copolymer films of polyvinylidene fluoride–trifluoroethylene (PVDF–TrFE 75/25) has been investigated via high-resolution real-space imaging of electrically induced domain structure evolution using resonance-enhanced piezoresponse force microscopy. It has been shown that in strongly imprinted films application of switching pulses of opposite polarity results in qualitatively different domain switching dynamics. A distinct feature of domain dynamics is roughening of the domains walls during switching to the preferred polarization state as opposed to smooth domain boundaries during switching to the opposite direction. The observed switching behavior is explained by a combined effect of the spatially uniform built-in electric field and local disorder potential. Application of the external potential changes the balance between the two and creates conditions under which domain growth is dominated either by the average built-in electric field or local random-bond disorder potential.