Large magnetodielectric response of PST/LSMO/LCMO film over a wide temperature range

Pb_0.6Sr_0.4TiO₃/La_0.7Sr_0.3MnO₃/La_0.7Ca_0.3MnO₃ (PST/LSMO/LCMO) film is grown on Si substrate by chemical solution deposition method. The film crystallizes perfectly into perovskite phases with a random crystalline orientation. The La_0.7Sr_0.3MnO₃/La_0.7Ca_0.3MnO₃/Si layer exhibits low resistivity and obvious negative magnetoresistivity (MR); the PST/LSMO/LCMO film shows notable magnetocapacitance (MC) above 350 K, from 102.9% to 29.5%. Near room temperature, there is no distinguished magnetoelectric coupling; the MC is 34.3% @ 250 K, 29.5% @ 300 K and 32.8% @ 350 K respectively. The mechanism can be explained in light of the Maxwell-Wagner (MW) model and the enhanced MR origin from the successive mixed manganite phases and spin dependent tunneling across the junctions of PST/LSMO/LCMO. This work provides a new approach for designing and developing novel composites with promising MC.