Strain-induced improvement of retention loss in PbZr0.2Ti0.8O3 films
Strain-induced improvement of retention loss in PbZr0.2Ti0.8O3 films
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DOI：
10.1063/1.4913421
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发表时间：
2015-02
影响因子：
4
通讯作者：
E. Guo;Robert Roth;Sujit Das;A. Herklotz;K. Dörr
中科院分区：
文献类型：
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作者：
E. Guo;Robert Roth;Sujit Das;A. Herklotz;K. Dörr
通过原位控制压电衬底产生的外延应变，研究了PbZr0.2Ti0.803薄膜中纳米磁畴的保持行为。我们的样品中的保留行为表现出强烈的极性依赖性：向上极化的磁区表现出极好的稳定性，而向下极化的磁区表现出伸展的指数衰减。面内压缩应变的可逆释放强烈地减少了保留损失，反映在松弛时间增加了一个数量级。我们初步将观察到的行为归因于La0.7Sr0.3MnO_3底电极界面的内置场与应变的关系，并可能进一步贡献于与应变有关的去极化场的屏蔽。我们的工作直接揭示了外延应变对降低铁电畴驰豫的重要性，这对非易失性存储器件等应用是不利的。
The retention behavior of nanoscale domains in PbZr0.2Ti0.8O3 thin films is investigated by in-situ controlling the epitaxial strain arising from a piezoelectric substrate. The retention behavior in our sample shows strong polarity-dependence: Upward-poled domains exhibit excellent stability, whereas downward-poled domains reveal a stretched exponential decay. Reversible release of in-plane compressive strain strongly reduced the retention loss, reflected in an enhancement of the relaxation time by up to one order of magnitude. We tentatively attribute the observed behavior to a strain dependence of the built-in field at the interface to the La0.7Sr0.3MnO3 bottom electrode, with a possible further contribution of strain-dependent screening of the depolarizing field. Our work directly reveals the importance of epitaxial strain for reducing ferroelectric domain relaxation which is detrimental for applications such as nonvolatile memory devices.