abstract
In this paper, we report a preparation of multiferroic heterostructure from thin film of Ni-Mn-Ga (NMG) alloy and lead magnesium niobate-lead titanate (PMN-PT) with effective magnetoelectric (ME) coupling between the film as ferromagnetic material and PMN-PT as piezoelectric material. The heterostructure was prepared by relatively low temperature (400 degrees C) deposition of the film on single crystal of piezoelectric PMN-PT substrate using rf magnetron co-sputtering of Ni50Mn50 and Ni50Ga50 targets. Magnetic measurements by Superconducting Quantum Interference Design (SQIUD) Magnetometer and Vibrating Sample Magnetometer (VSM) on the film revealed that the film is in ferromagnetically ordered martensitic state at room temperature with saturation magnetization of similar to 240 emu/cm(3) and Curie temperature of similar to 337 K. Piezoresponse force microscopy (PFM) measurement done at room temperature on the substrate showed the presence of expected hysteresis loop confirming the stability of the piezoelectric state of the substrate after deposition. Room temperature ME voltage coefficient (alpha(ME)) of the heterostructure was measured as a function of applied bias dc magnetic field in Longitudinal-Transverse( L-T) ME coupling mode by lock-in technique. A maximum ME coefficient alpha ME of 3.02mV/cm Oe was measured for multiferroic NMG/PMN-PT heterostructure which demonstrates that there is ME coupling between the film as ferromagnetic material and PMN-PT as piezoelectric material. (C) 2012 Elsevier B.V. All rights reserved.
keywords
SHAPE-MEMORY; SINGLE-CRYSTALS; DEPOSITION; COMPOSITE; STRAIN
subject category
Materials Science; Physics
authors
Teferi, MY; Amaral, VS; Lounrenco, AC; Das, S; Amaral, JS; Karpinsky, DV; Soares, N; Sobolev, NA; Kholkin, AL; Tavares, PB
our authors
Andrei Kholkin
Principal Researcher
Armando António Cardoso Dos Santos Lourenço
Assistant Professor
Dzmitry Karpinski (Karpinsky)
Post-doc Fellowship
João Cunha de Sequeira Amaral
Assistant Researcher
Vitor Brás Sequeira Amaral
Full professoracknowledgements
The author is grateful to FCT for partial financial support (under grant no's: SFRH/BD/25011/2005, SFRH/BPD/63942/2009, SFRH/BPD/39262/2007, and SFRH/BPD/42506/2007) as well as to the financial support from Erasmus Mundus Programme (EU) to carry out this work at University of Aveiro (UA).