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Magnetic Properties and Impedance Spectroscopic Studies of Multiferroic Bi1-xNdxFeO3 Materials

In this work, we report the Nd-doping effect on structural, magnetic, and complex impedance properties of BFO materials. With the presence of Nd, the crystal structure of BFO was changed. Weak ferromagnetism was observed with an enhancement of spontaneous magnetization due to the collapse of the spin cycloid structure. | ISSN Print 1226-1750 ISSN Online 2233-6656 Journal of Magnetics 21 1 29-34 2016 http dx.doi.org 10.4283 JMAG.2016.21.1.029 Magnetic Properties and Impedance Spectroscopic Studies of Multiferroic Bi1-xNdxFeO3 Materials Dao Viet Thang1 2 Du Thi Xuan Thao2 and Nguyen Van Minh1 1 Center for Nano Science and Technology Hanoi National University of Education 136 Xuan Thuy Road Hanoi Vietnam 2 Department of Physics Hanoi University of Mining and Geology Duc Thang Ward North Tuliem Districs Hanoi Vietnam Received 22 July 2015 Received in final form 22 December 2015 Accepted 22 December 2015 Nd-doped BiFeO3 materials were synthesized via a sol gel method. The crystal structure magnetic properties and complex impedance spectroscopy of multiferroic Bi1-xNdxFeO3 BNFO materials were investigated by X- ray diffraction XRD Raman scattering vibrating sample magnetometer VSM and complex impedance spectroscopy. Our results show that the lattice crystal constants a c and the ratio c a of BNFO materials decreased with increasing Nd concentration. All samples exhibited weak ferromagnetism at room temperature and the magnetization of samples was enhanced by the presence of Nd3 ions. There was an enhancement in the spontaneous magnetization of BFO with increasing Nd concentration which is attributable to the collapse of the spin cycloid structure. Keywords multiferroic Raman Nd-doped magnetization impedance 1. Introduction netic interactions such as Ho3 -Ho3 and Ho3 -Fe3 in addition to the regular Fe3 -Fe3 interaction. Furthermore BiFeO3 BFO material is multiferroic because it exhibits these interactions contribute to the higher magnetization both ferroelectric and antiferromagnetic properties 1 . It values in comparison to the other non-magnetic rare also exhibits magneto-electric coupling in which mag- earth-doping systems. The antisymmetric Dzyaloshinskii netization is induced by an electric field and electric Moriya exchange interaction between neighboring spins polarization is .