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The multiferroic Bi0.8Gd0.1M0.1Fe0.9Ti0.1O3, (where M = Ba (DB), La (DL) and Pb (DP)) has been synthesized by using solid-state reaction technique. Effects of Ba, La and Pb substitution on the structure, electrical and ferroelectric properties of Bi0.8Gd0.1M0.1Fe0.9Ti0.1O3 samples have been studied by performing X-ray diffraction, dielectric and magnetic measurements. The crystal structures of the ceramic samples have a tetragonal phase. The vibrating sample magnetometer (VSM) measurement shows a significant change in the magnetic properties of Ba-doped Bi0.8Gd0.1M0.1Fe0.9Ti0.1O3 as compared to La- and Pb-doped ceramics. It is seen that coercive field (HC) and remanent magnetization (MR) increases with Ba-doped ceramics but decreases for La- and Pb-doped ceramics.

In this paper, a systematic investigation has been done to study the effect of variation in annealing temperature on magnetic and optical properties of Mn-doped SnO2. Coprecipitation technique has been used to synthesize Sn1-xMnxO2 samples with low Mn concentration (2%). Pristine SnO2 is sintered at 350 °C. Mn-doped SnO2 samples are sintered at 350, 450, 550 and 650 °C. The structures of tetragonal rutile of SnO2 and Mndoped SnO2 have been confirmed by the XRD pattern. Typical ferromagnetic ordering has been observed for Mn-doped SnO2 samples annealed at different temperatures. However, on increasing the annealing temperature saturation magnetization as well as the coercive field decreases, indicating a crucial phase transformation from ferromagnetism to paramagnetism. UV-Vis spectroscopy shows increase in absorbance and a slight shift in the absorption edge with Mn-doping at increasing annealing temperature indicating shifting of absorption peak towards higher wavelength. Tauc's plot has been used to find the optical band gap (Eg). [ABSTRACT FROM AUTHOR]

The consequences of swift heavy ion (SHI) irradiation (Li3 + , 50 MeV, fluence = 5 × 1013 ions/cm2) on the structural and microscopic magnetic properties of Y3 + -substituted yttrium iron garnet (Y3 + x Fe5 − x O12, x = 0.0, 0.2 and 0.4) have been studied at 300 K. It is found that an additional YFeO3-phase observed along with bcc garnet phase, is completely removed for x = 0.2 composition while its percentage formation considerably reduces for x = 0.4 composition after irradiation. Similar effect has been observed for specimens sintered at 1,500°C. The SHI-induced ion beam mixing has been revealed through X-ray diffraction and Mössbauer spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: In the present study, barium hexaferrite powders were prepared by ordinarily mixing and by high energy ball-milling stoichiometric amounts of the BaCO3 and Fe2O3 precursors, followed by heat treatments carried out in the 900–1100°C range of temperature. The structural and magnetic properties of the resulting powders were analyzed by differential thermal analysis, X-ray diffraction, scanning electron microscopy, Mössbauer spectroscopy and magnetization measurements. The milled powder showed a lower decomposition temperature and higher surface area than the ordinarily mixed powder. Formation of the BaFe2O4 intermediate phase was observed in conventionally prepared hexaferrites. Diversely, the mechanical process before annealing allowed for the hexaferrite formation at much lower temperatures but without formation of intermediate phases. The hyperfine parameters showed to be independent of the processing method. Higher saturation magnetization, and coercivity were observed in the barium hexaferrites prepared by high energy ball milling. [Copyright &y& Elsevier]

In the present study, iron-containing pyrochlores of the A2FeBO7 type (where A = Y, Gd, Eu and Dy; B = Sb and Nb) were synthesized by solid-state reaction of precursor oxides. The compounds were structurally and magnetically characterized by X-ray diffraction, Mössbauer spectroscopy and magnetic measurements. The results revealed that the crystallographic structures and magnetic properties depend, basically, on the type of B atoms. [ABSTRACT FROM AUTHOR]