Zhao Ying-Ying, Wang Jing, Kuang Hao, Hu Feng-Xia, Liu Yao, Wu Rong-Rong, Zhang Xi-Xiang, Sun Ji-Rong, Shen Bao-Gen
Beijing National Laboratory for Condensed Matter Physics and the State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P. R. China.
Physical Science and Engineering, King Abdullah Univ Sci &Technol, Thuwal 23955-6900, Saudi Arabia.
Sci Rep. 2015 Apr 24;5:9668. doi: 10.1038/srep09668.
Memory effect of electric-field control on magnetic behavior in magnetoelectric composite heterostructures has been a topic of interest for a long time. Although the piezostrain and its transfer across the interface of ferroelectric/ferromagnetic films are known to be important in realizing magnetoelectric coupling, the underlying mechanism for nonvolatile modulation of magnetic behaviors remains a challenge. Here, we report on the electric-field control of magnetic properties in wide-band (011)-Pr0.7Sr0.3MnO3/0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 heterostructures. By introducing an electric-field-induced in-plane anisotropic strain field during the cooling process from room temperature, we observe an in-plane anisotropic, nonvolatile modulation of magnetic properties in a wide-band Pr0.7Sr0.3MnO3 film at low temperatures. We attribute this anisotropic memory effect to the preferential seeding and growth of ferromagnetic (FM) domains under the anisotropic strain field. In addition, we find that the anisotropic, nonvolatile modulation of magnetic properties gradually diminishes as the temperature approaches FM transition, indicating that the nonvolatile memory effect is temperature dependent. By taking into account the competition between thermal energy and the potential barrier of the metastable magnetic state induced by the anisotropic strain field, this distinct memory effect is well explained, which provides a promising approach for designing novel electric-writing magnetic memories.
电场控制对磁电复合异质结构中磁行为的记忆效应长期以来一直是一个备受关注的课题。尽管已知压电应变及其在铁电/铁磁薄膜界面的传递在实现磁电耦合中很重要,但磁行为非易失性调制的潜在机制仍然是一个挑战。在此,我们报道了宽带(011)-Pr0.7Sr0.3MnO3/0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3异质结构中磁性能的电场控制。通过在从室温冷却过程中引入电场诱导的面内各向异性应变场,我们在低温下观察到宽带Pr0.7Sr0.3MnO3薄膜中磁性能的面内各向异性、非易失性调制。我们将这种各向异性记忆效应归因于在各向异性应变场下铁磁(FM)畴的优先形核和生长。此外,我们发现随着温度接近FM转变,磁性能的各向异性、非易失性调制逐渐减弱,这表明非易失性记忆效应与温度有关。通过考虑热能与各向异性应变场诱导的亚稳磁态势垒之间的竞争,这种独特的记忆效应得到了很好的解释,这为设计新型电写入磁存储器提供了一种有前景的方法。