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arXiv · 2509.00382

Role of lattice structure and breaking of antiferromagnetic spin order in enhancement of ferromagnetic, electronic, and magneto-electric properties in Fe$_{2-x}$Sc$_x$O$_3$ system

R. N. Bhowmik·Bipin Kumar Parida·Amit Kumar·P. D. Babu·S. M. Yusuf
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Abstract

The strategy of breaking antiferromagnetic (AFM) ground state in alpha-Fe2O3 by doping non-magnetic Sc3+ ions at the Fe3+ sites has been used in Fe2-xScxO3 system (x = 0.2-1.0). The material has been stabilized in single-phase (rhombohedral alpha-Fe2O3) or mix-phase (rhombohedral alpha-Fe2O3 and cubic Sc2O3-types) structure by varying Sc content and heat treatment temperature. Neutron diffraction confirmed perturbed AFM ground state down to low temperature with magnetic moment 2.75-4.68 muB per Fe site and Morin transition 260 K. DC magnetic measurement showed magnetic coercivity 0.2 to 6 kOe. The material showed transformation from insulating state (conductivity 10-14-10-10 S per cm and polarization 0.5-2 micro-C per cm2) to high conductive state (conductivity 10-10 -10-7 S per cm and polarization greater than 2 micro-C per cm2) above the Morin transition. The room temperature measurements showed maximum current density 35-186 micro-A per cm2, electric polarization 2.7-15.6 micro-C per cm2, magneto-electric voltage up to 5 mV with coupling constant 0.62-10.11 mV per Oe.cm and magneto-conductance up to 90 %. The results will open the door for suitably modifying the lattice-structure, magnetic spin order, and charge-spin coupling in hematite based material and their application in low power spintronic devices.

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R. N. Bhowmik, Bipin Kumar Parida, Amit Kumar, P. D. Babu, S. M. Yusuf. 2025-08-30. Role of lattice structure and breaking of antiferromagnetic spin order in enhancement of ferromagnetic, electronic, and magneto-electric properties in Fe$_{2-x}$Sc$_x$O$_3$ system. https://arxiv.org/abs/2509.00382

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