电场调控Pt/Co∶ZnO/Nb∶SrTiO_3异质结阻变与磁性研究

利用脉冲激光沉积法在0.7%Nb∶SrTiO_3衬底上制备了Co∶ZnO薄膜,并构建了Pt/Co∶ZnO/Nb∶SrTiO_3异质结器件。该器件表现出典型的双极性阻变效应,在正、负向电压作用下,器件电阻可以在低阻态和高阻态之间变换,电阻变换比值可达到104,阻态具有一定的保持性与耐久性,同时Co∶ZnO薄膜的饱和磁化强度会产生与阻变相关联的可逆调控。结合ZnO薄膜阻变与磁性调控结果发现,氧空位在Co∶ZnO/Nb∶SrTiO_3异质结的阻变及磁性调控中具有重要作用,并采用氧空位产生与湮灭结合载流子注入-束缚/解束缚模型解释阻变与磁性调控。

The Electric-Field Controllable Non-Volatile 35° Rotation of Magnetic Easy Axis in Magnetoelectric CoFeB/(001)-Cut Pb(Mg_(1/3)Nb_(2/3))O_3-25%PbTiO_3 Heterostructure

Using in situ electric-field-modulated anisotropic magnetoresistance measurement, a large reversible and non- volatile in-plane rotation of magnetic easy axis of -35° between the positive and negative electrical poling states is demonstrated in C040Fe40B20//（001）-cut Pb（Mgl/3Nb2/3）O3-25PbTiO3 （PMN-PT）. The specific magneto- electric coupling mechanism therein is experimentally verified to be related to the synchronous in-plane strain rotation induced by 109° ferroelastic domain switching in the （001）-cut PMN-PT substrate.

Pt/NiO/Nb:SrTiO3异质结的阻变、光响应及磁性

利用脉冲激光沉积法在Nb:SrTiO3(NSTO)单晶衬底上制备了NiO薄膜并构筑了Pt/NiO/NSTO异质结器件。该器件表现出典型的双极性阻变行为,具有多级电阻变换特性和优异的保持与翻转性能。在光照作用下,器件高阻态(high resistance state,HRS)的电阻值减小到暗场下电阻值的约1/100,而低阻态(low resistance state,LRS)的阻值无明显变化。对器件磁性的研究表明,LRS下的饱和磁化强度明显高于初始态(initial state,IS)和HRS下的饱和磁化强度。这些结果归因于NiO/NSTO界面的电子注入束缚/解束缚和氧空位迁移。该器件在非易失性多级存储、光敏、磁电等多功能器件中有潜在的应用价值。