Article,
Composition-dependent spin exchange interaction for multiferroicity in perovskite Pb(Fe1/2Nb1/2)O3
Affiliations
- [1] Ulsan National Institute of Science and Technology [NORA names: South Korea; Asia, East; OECD];
- [2] University of Technology Sydney [NORA names: Australia; Oceania; OECD];
- [3] Pohang University of Science and Technology [NORA names: South Korea; Asia, East; OECD];
- [4] Korea Institute of Materials Science [NORA names: South Korea; Asia, East; OECD];
- [5] Pukyong National University [NORA names: South Korea; Asia, East; OECD];
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Abstract
The composition-dependent spin exchange interaction in a perovskite-structured Pb(Fe0.5−xNix)Nb1/2O3 system has been studied to understand its multiferroicity at room-temperature. Special emphasis was paid to the magnetic behavior in terms of magnetic moment, interatomic distance, and atomic ordering because they play a key role in the modulation of magnetic multiferroic behavior. We observed that 10 mol. % Ni incorporation led to multiferroic behavior with considerable ferrimagnetic properties (saturation magnetization of 0.6 emu/g and a coercive field of 20 Oe) coupled with the inherent properties of displacive ferroelectricity (spontaneous polarization of 20 μC/cm2). A subsequent increase in the Ni substitution degree degraded the ferroelectricity due to a phase transition from a non-centrosymmetric rhombohedral to a centrosymmetric cubic system. We have shown that magnetic spins with a pronounced magnetic moment along the [001] direction are ferrimagnetically arranged when the interatomic distance between the magnetic transition metals at the octahedral site is less than 4 Å, resulting in significant magnetic properties The objective of this study is to provide a general methodology for modulating magnetic orders in ferroelectric perovskite oxides.