Enhanced electromagnetic tunability of barium strontium titanate films via coating Pr modified yttrium iron garnet layer

It is hard to simultaneously realize the high dielectric tunability and low loss for the single Ba0.6Sr0.4TiO3 (BST) dielectric film made through chemical method. Garnet structured Y2.80Pr0.20Fe5O12 (YPrIG) exhibits the merits of high saturation magnetization and a much high resistivity, which are helpful for realizing magnetoelectric double tuning and suppressing the dielectric loss of BST film. In this work, Y2.80Pr0.20Fe5O12/Ba0.6Sr0.4TiO3 (YPrIG/BST) composite films were fabricated by sol-gel method. The composite films exhibited a low dielectric loss (0.0087), and got a magnetic tunability of 11.73% at 10 kOe and 1.44 MHz. Compared with BST film, the tunability of YPrIG/BST film was enhanced from 56.25% to 73.24% under the bias electric field of 800 kV/cm. Additionally, YPrIG/BST films exhibited an electromagnetic double adjustability. The electromagnetic tunability of YPrIG/BST composite films was as high as 80.40% at 1.44 MHz, under the DC bias electric field of 800 kV/cm and magnetic field of 10 kOe. This phenomenon can be explained in terms of the superposition effect of electric field and magnetic field.