Song Guoqiang, Zhang Yuanyuan, Li Sheng, Yang Jing, Bai Wei, Tang Xiaodong
Key Laboratory of Polar Materials and Devices, Ministry of Education, Department of Electronic Science, East China Normal University, Shanghai 200241, China.
Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China.
Nanomaterials (Basel). 2021 Apr 25;11(5):1109. doi: 10.3390/nano11051109.
The BaTiO (BTO)/LaSrMnO (LSMO) magnetoelectric composite films were prepared by sol-gel method on STO (001) substrates. The heterojunction has highly preferred orientation and exhibits well ferroelectric properties with perfect hysteresis loops and microscopic polarization switch behaviors. The most interesting thing is the abnormal dielectric relaxation phenomenon in the dielectric spectra at high frequency range and around the phase transition temperature of LSMO. By analyzing the resistance properties of LSMO films, it is indicated that charge-based interfacial coupling, Maxwell-Wagner effect due to the JT polaron and fast resistivity rise in LSMO layer is the main reason. This work emphasizes the crucial role of resistivity exchanges and of carrier accumulation at interfaces for the application of magnetoelectric heterojunction.
采用溶胶-凝胶法在STO(001)衬底上制备了BaTiO(BTO)/LaSrMnO(LSMO)磁电复合薄膜。该异质结具有高度择优取向，表现出良好的铁电性能，具有完美的磁滞回线和微观极化开关行为。最有趣的是在高频范围以及LSMO的相变温度附近的介电谱中出现的异常介电弛豫现象。通过分析LSMO薄膜的电阻特性表明，基于电荷的界面耦合、JT极化子引起的麦克斯韦-瓦格纳效应以及LSMO层中电阻率的快速上升是主要原因。这项工作强调了电阻率交换和界面处载流子积累在磁电异质结应用中的关键作用。
