Room-temperature magnetoelectric coupling in nanocrystalline nanocrystalline Pr_2Ti_2O_7

摘要

Rare-earth titanate monoclinic nanocrystalline Pr_2Ti _2O_7 was prepared by the sol-gel method. The nanocrystalline Pr_2Ti_2O_7 pellets present room temperature ferromagnetism. Vacuum annealing enhances ferromagnetism which disappears for the pellet with subsequent long time air-annealing, indicating that the observed ferromagnetism is connected with the oxygen vacancies. The Pr_2Ti_2O_7 pellets annealed at 1000 C for 1 h show the coexistence of ferromagnetism and ferroelectricity at room temperature. The room-temperature magnetodielectric effect was observed in Pr _2Ti_2O_7 pellets. In addition, the electric field treatment leads to an enormous enhancement of saturation magnetization for Pr_2Ti_2O_7 multiferroic pellet, showing a strong magnetoelectric coupling.