Magneto-dielectric signature of Gd3+-substituted PbMg1/3Nb2/3O3 ceramics

• Published in: Journal of materials science. Materials in electronics 2023-06, Vol.34 (17), p.1349, Article 1349
• Main Authors: Pandey, Adityanarayan H., Gupta, S. M., Sahlot, P., Awasthi, A. M., Chandrasekhar Rao, T. V., Nigam, A. K.
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Deviation; Dielectric strength; Electrostriction; Ferroelectricity; Gadolinium; Low temperature; Magnesium niobates; Magnetic permeability; Magnetization; Magnetostriction; Materials Science; Optical and Electronic Materials; Polar environments; Substitutes; Subsystems; Temperature; Temperature scales
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-023-10769-0

The compound lead magnesium niobate (PMN) is a well-known relaxor ferroelectric depicting frequency-dependent dielectric maximum below ~ 250 K. The temperature and field dependences of ac/dc magnetization reveal magneto-dielectric signatures in Gd-doped PMN ceramic. The inverse magnetic susceptibility shows deviation from linear behavior on cooling, and ac susceptibility shows peak at ~ 125 K, indicating the formation of local magnetic-interacting areas, which are different from polar clusters formed at higher temperatures. However, low-temperature magnetization versus magnetic field (MH) curve described by all the samples is well elucidated by the Brillouin functions suggesting weak deviations due to some magneto-electric interaction. For higher Gd-doped PMN ( x  > 0.05), local interaction between the magnetic polar regions are believed to occur, where both Pb and Mg sites are substituted by Gd ions in the lattice. This result is the first strong evidence of both magnetic and polar interacting regions in this family of materials, where the temperature scales of two phenomena are different. The interaction between the two subsystems via electrostriction and magnetostriction leads to weak magneto-dielectric effect.