Structural, Electronic, and Magnetic Analysis and Device Characterization of Ferroelectric-Ferromagnetic Heterostructure (BZT-BCT/LSMO/LAO) Devices for Multiferroic Applications


Ferroelectricity and ferromagnetism have been investigated in a lead-free 0.5Ba(Zr 0.2 Ti 0.8 )O 3 -0.5(Ba 0.7 Ca 0.3 )TiO 3 (BZT-BCT)/La 0.7 Sr 0.3 MnO 3 (LSMO) heterostructure for multiferroic (MF) applications. The BZT-BCT thin film has been grown on LSMO/lanthanum aluminate, LaAlO 3 (LAO) by pulsed laser deposition (PLD). Prior to that, the LSMO layer was deposited on a single-crystal LAO substrate by PLD. The epitaxial growth of the (001) oriented films was confirmed by X-ray diffraction analysis. The small value of the full-width at half-maximum of the rocking curve peak (0.1°) performed about (002) plane of the BZT-BCT film indicates an out-of-plane orientation of the film. The polarization switching behavior in the heterostructure device was observed with a remnant polarization of ~47 μC/cm 2 and a coercive field of ~180kV/cm at an applied voltage of 5 V. The frequency-dependent relative dielectric constant varies in-between 5100 and 4900 in the frequency range from 1 to 50 kHz during the dielectric measurements of the fabricated device. The observed low value of the dielectric loss (0.02) confirms the outstanding quality of the ferroelectric device. A well-saturated room temperature magnetization-applied field curve, with a coercive field of ~1200A/m and a remnant magnetization of ~110kA/m, was observed in the LSMO/LAO system indicating the ferromagnetic behavior of the film. The temperature-dependent magnetization of the LSMO film exhibits a ferromagnetic-to-paramagnetic transition at ~360K. These results on all solid-state ferroelectric-ferromagnetic heterostructure using BZT-BCT and LSMO open viable possibilities for MF applications.


Physics, Astronomy, and Materials Science

Document Type





Dielectric losses, ferroelectric capacitor, leakage currents, magnetoelectric coupling, polarization switching

Publication Date


Journal Title

IEEE Transactions on Magnetics