Optical, ferroelectric and magnetic properties of multiferroelectric BiFeO3-(K0.5Na0.5)0.4(Sr0.6Ba0.4)0.8Nb2O6 thin films
- a Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong. Fax:852-2333-7629, Tel:852-2766-5669, email:apaclmak@polyu.edu.hk
- b Advanced Nanofabrication, Imaging and Characterization Core Lab, King Abdullah University of Science and Technology, Thuwal, Jeddah, Saudi Arabia. Fax:966-2-8021174, Tel:966-2-8084569, email: yingbang.yao@kaust.edu.sa
- Received 2 July 2013
- Revised 10 October 2013
- Accepted 11 October 2013
- Available online 22 October 2013
Highlights
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multiferroic BiFeO3-(K0.5Na0.5)0.4(Sr0.6Ba0.4)0.8Nb2O6 (BFO-KNSBN) trilayer thin films were fabricated.
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Their ferroelectric, magnetic, dielectric and optical properties were investigated.
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The ferroelectric polarization and dielectric constant of the films were enhanced by introducing KNSBN as a barrier layer.
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A double hysteresis magnetic loop was observed in the KNSBN-BFO-KNSBN trilayer films.
Abstract
Multiferroic BiFeO3-(K0.5Na0.5)0.4(Sr0.6Ba0.4)0.8Nb2O6 (BFO-KNSBN) trilayer thin films, were epitaxially grown on MgO(001) and SrTiO3(001) by using pulsed laser deposition (PLD). Their ferroelectric, magnetic, dielectric and optical properties were investigated. It was found that both ferroelectric polarization and dielectric constant of the films were enhanced by introducing KNSBN as a barrier layer. Meanwhile, ferromagnetism of BFO was maintained. More interestingly, a double hysteresis magnetic loop was observed in the KNSBN-BFO-KNSBN trilayer films, where exchange bias and secondary phase in the BFO layer played crucial roles. Interactions between adjacent layers were revealed by temperature-dependent Raman spectroscopic measurements.