Magnetoelectric Coupling Induced Orbital Reconstruction And Ferromagnetic Insulating State In Pbzr0.52ti0.48o3/La0.67sr0.33mno3 Heterostructures

Novel phenomena at the ferromagnetic/ferroelectric interface have generated much interest. Here, a ferromagnetic insulating state with the Curie temperature about 268-286 K in PbZr0.52Ti0.48O3/La0.67Sr0.33 MnO3 heterostructures is induced and modulated by varying the PbZr0.52Ti0.48O3 thickness. An abnormally enlarged c/a ratio in La0.67Sr0.33MnO3 by strain-based coupling effect leads to d(3z2-r2) orbital preferable occupancy. This orbital reconstruction modulates effective electron transfer and finally leads to a ferromagnetic insulating state. Valence change induced by charge-based coupling effect could be partially responsible for change in the Curie temperature in the strongly correlated electron system of La1-xSrxMnO3. This work provides a deeper understanding of strain effects near the ferromagnetic/ferroelectric interface, especially in a PbZr1-yTiyO3/La1-xSrxMnO3 heterostructure system.