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Papers by Swarnali Hait
Physica Scripta, Aug 21, 2023
Journal of Physics: Condensed Matter
Gallium ferrite (GFO) is a magnetoelectric (ME) material, capturing growing attention due to its ... more Gallium ferrite (GFO) is a magnetoelectric (ME) material, capturing growing attention due to its strong ME coupling at room temperature. However, the application of the material in practical use is hindered due to its high leakage. In this work, the effects of cobalt (Co) substitution at the iron (Fe) sites of GaFe1−x Co x O3 (0.0 ⩽ x ⩽ 0.1) polycrystals on the structure, electric and magnetic properties are investigated in detail. 5 at. wt.% substitution (x = 0.05) with cobalt ions achieves a reduction in leakage current density by four orders of magnitude due to reduced hopping between Fe3+ and Fe2+ ions and suppression of the oxygen vacancy formation. This is supported by higher dielectric constant and lower dielectric loss, as well as a significant difference between grain and grain boundary resistances. Two-phase-like magnetic behavior in magnetic hysteresis loop with enhanced magnetization and two magnetic transition temperatures are observed in the doped samples. All samples ...
IEEE Transactions on Magnetics
AIP Advances
Multiferroic materials with good magneto-electric coupling are of great interest due to their eno... more Multiferroic materials with good magneto-electric coupling are of great interest due to their enormous applications in the field of spintronic devices. Magnetoelectric (ME) gallium ferrite is an interesting material due to its room temperature (RT) piezoelectricity and near RT ferrimagnetism along with significant ME coupling (10−11 s/m at 4.2 K). The work aims to increase the magnetic transition temperature (TC) of the material above RT so that the material can have strong ME coupling at room temperature and can be implemented for practical applications. Several earlier reports have shown the magnetic transition temperature of Ga2−xFexO3 increases with higher Fe contents. Hence, we chose to study the properties of Ga2−xFexO3 (GFO) only for x = 1.2. Y3Fe5O12 (YIG) is another material that is RT ferromagnet material with very high resistivity (∼1012 Ω cm). In this work, by forming a GFO-YIG composite with only a 10% concentration of YIG, the phase transition temperature is increased ...
Physica B: Condensed Matter
Journal of Alloys and Compounds, 2020
Abstract Barium (Ba) doping at Bismuth (Bi) site is reported to enhance magnetic properties of Bi... more Abstract Barium (Ba) doping at Bismuth (Bi) site is reported to enhance magnetic properties of Bismuth Ferrite (BiFeO3) while Yttrium (Y) doping at the same is found to improve ferroelectric and dielectric properties. To investigate the combined effect of Ba and Y co-doping, Ba0.1Bi0.9-xYxFeO3 (x = 0.0, 0.1 and 0.2) are synthesized using chemical synthesis route and their magnetoelectric and dielectric properties are studied in detail. The X-Ray Diffraction study confirms the single phase nature of the synthesized samples. The ferroelectric property is enhanced for x = 0.1 while the magnetic studies show enhanced magnetisation for both co-doped samples with highest enhancement in x = 0.1. The doped samples exhibit a first order field induced metamagnetic transition. The dielectric constant also increases with reduced tangent loss and conductivity for x = 0.1. Therefore, co-doping with Ba and Y improves the magnetoelectric and dielectric property of BiFeO3.
Journal of Alloys and Compounds, 2020
Barium (Ba) doping at Bismuth (Bi) site is reported to enhance magnetic properties of Bismuth Fer... more Barium (Ba) doping at Bismuth (Bi) site is reported to enhance magnetic properties of Bismuth Ferrite (BiFeO 3) while Yttrium (Y) doping at the same is found to improve ferroelectric and dielectric properties. To investigate the combined effect of Ba and Y co-doping, Ba 0.1 Bi 0.9-x Y x FeO 3 (x ¼ 0.0, 0.1 and 0.2) are synthesized using chemical synthesis route and their magnetoelectric and dielectric properties are studied in detail. The X-Ray Diffraction study confirms the single phase nature of the synthesized samples. The ferroelectric property is enhanced for x ¼ 0.1 while the magnetic studies show enhanced magnetisation for both co-doped samples with highest enhancement in x ¼ 0.1. The doped samples exhibit a first order field induced metamagnetic transition. The dielectric constant also increases with reduced tangent loss and conductivity for x ¼ 0.1. Therefore, co-doping with Ba and Y improves the magnetoelectric and dielectric property of BiFeO 3 .
Books by Swarnali Hait
Physica Scripta, Aug 21, 2023
Journal of Physics: Condensed Matter
Gallium ferrite (GFO) is a magnetoelectric (ME) material, capturing growing attention due to its ... more Gallium ferrite (GFO) is a magnetoelectric (ME) material, capturing growing attention due to its strong ME coupling at room temperature. However, the application of the material in practical use is hindered due to its high leakage. In this work, the effects of cobalt (Co) substitution at the iron (Fe) sites of GaFe1−x Co x O3 (0.0 ⩽ x ⩽ 0.1) polycrystals on the structure, electric and magnetic properties are investigated in detail. 5 at. wt.% substitution (x = 0.05) with cobalt ions achieves a reduction in leakage current density by four orders of magnitude due to reduced hopping between Fe3+ and Fe2+ ions and suppression of the oxygen vacancy formation. This is supported by higher dielectric constant and lower dielectric loss, as well as a significant difference between grain and grain boundary resistances. Two-phase-like magnetic behavior in magnetic hysteresis loop with enhanced magnetization and two magnetic transition temperatures are observed in the doped samples. All samples ...
IEEE Transactions on Magnetics
AIP Advances
Multiferroic materials with good magneto-electric coupling are of great interest due to their eno... more Multiferroic materials with good magneto-electric coupling are of great interest due to their enormous applications in the field of spintronic devices. Magnetoelectric (ME) gallium ferrite is an interesting material due to its room temperature (RT) piezoelectricity and near RT ferrimagnetism along with significant ME coupling (10−11 s/m at 4.2 K). The work aims to increase the magnetic transition temperature (TC) of the material above RT so that the material can have strong ME coupling at room temperature and can be implemented for practical applications. Several earlier reports have shown the magnetic transition temperature of Ga2−xFexO3 increases with higher Fe contents. Hence, we chose to study the properties of Ga2−xFexO3 (GFO) only for x = 1.2. Y3Fe5O12 (YIG) is another material that is RT ferromagnet material with very high resistivity (∼1012 Ω cm). In this work, by forming a GFO-YIG composite with only a 10% concentration of YIG, the phase transition temperature is increased ...
Physica B: Condensed Matter
Journal of Alloys and Compounds, 2020
Abstract Barium (Ba) doping at Bismuth (Bi) site is reported to enhance magnetic properties of Bi... more Abstract Barium (Ba) doping at Bismuth (Bi) site is reported to enhance magnetic properties of Bismuth Ferrite (BiFeO3) while Yttrium (Y) doping at the same is found to improve ferroelectric and dielectric properties. To investigate the combined effect of Ba and Y co-doping, Ba0.1Bi0.9-xYxFeO3 (x = 0.0, 0.1 and 0.2) are synthesized using chemical synthesis route and their magnetoelectric and dielectric properties are studied in detail. The X-Ray Diffraction study confirms the single phase nature of the synthesized samples. The ferroelectric property is enhanced for x = 0.1 while the magnetic studies show enhanced magnetisation for both co-doped samples with highest enhancement in x = 0.1. The doped samples exhibit a first order field induced metamagnetic transition. The dielectric constant also increases with reduced tangent loss and conductivity for x = 0.1. Therefore, co-doping with Ba and Y improves the magnetoelectric and dielectric property of BiFeO3.
Journal of Alloys and Compounds, 2020
Barium (Ba) doping at Bismuth (Bi) site is reported to enhance magnetic properties of Bismuth Fer... more Barium (Ba) doping at Bismuth (Bi) site is reported to enhance magnetic properties of Bismuth Ferrite (BiFeO 3) while Yttrium (Y) doping at the same is found to improve ferroelectric and dielectric properties. To investigate the combined effect of Ba and Y co-doping, Ba 0.1 Bi 0.9-x Y x FeO 3 (x ¼ 0.0, 0.1 and 0.2) are synthesized using chemical synthesis route and their magnetoelectric and dielectric properties are studied in detail. The X-Ray Diffraction study confirms the single phase nature of the synthesized samples. The ferroelectric property is enhanced for x ¼ 0.1 while the magnetic studies show enhanced magnetisation for both co-doped samples with highest enhancement in x ¼ 0.1. The doped samples exhibit a first order field induced metamagnetic transition. The dielectric constant also increases with reduced tangent loss and conductivity for x ¼ 0.1. Therefore, co-doping with Ba and Y improves the magnetoelectric and dielectric property of BiFeO 3 .