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

Abstract

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.