Articles you may be interested inCrystal structure and magnetic properties of Bi0.8A0.2FeO3 (A = La, Ca, Sr, Ba) multiferroics using neutron diffraction and Mossbauer spectroscopy AIP Advances 4, 087121 (2014); 10.1063/1.4893241Effect of Pr-and Nd-doping on structural, dielectric, and magnetic properties of multiferroic Bi0.8La0.2Fe0.9Mn0.1O3Polycrystalline multiferroic La 0.8 Bi 0.2 Fe 1−x Mn x O 3 ͑0.0Յ x Յ 0.4͒ samples were synthesized by the conventional solid state reaction method. Reitveld refinement of the x-ray diffraction patterns confirms the single phase character of all the compositions with orthorhombic structure having space group Pnma ͑No. 62͒. Dielectric properties of the samples at temperatures 200-475 K and frequencies 500 kHz-1 MHz authenticate the stabilization of ferroelectric phase with Mn substitution. Dielectric responses of these multiferroics have been analyzed carefully, in the light of "universal dielectric response" model. While cooling from room temperature to 20 K, systematic shifts in magnetization hysteresis loops indicate the presence of exchange bias ͑EB͒ phenomenon in the system. Magnetic behavior of these samples has been briefly discussed on the basis of "EB" model for granular systems. Temperature and magnetic field dependent magnetization data demonstrate enhanced magnetization due to the Mn substitution. Magnetocapacitance measurement reveals the magnetoelectric coupling for wide range of temperature ͑180-280 K͒ and decrease in dielectric loss at high magnetic field ͑3 T͒.

We report the electronic structure studies of well-characterized La0.8Bi0.2Fe1−x Mn x O3 (LBFM, 0.0 ⩽ x ⩽ 0.4) multiferroic samples investigated by soft x-ray absorption spectroscopy at O K-, Mn L3,2-, Mn K-, Fe L3,2- and La M4,5-edges along with the spectra of reference compounds. The investigations are performed to find out the chemical states and crystal field symmetry of ions present in the LBFM multiferroic samples after the substitution of Mn ions at Fe sites. Studies reveal a slight shift in the peak positions of O K-edge spectra along with growth in intensities of low-energy features. An analysis of the Mn L3,2- and K-edge, in addition to the comparison with the spectra of reference compounds, indicates that the Mn ions are present in mixed valence states. It is found that the Mn ions are mainly in +3 states along with a small contribution of +2 and +4 ones. The study of Fe L3,2-edge confirms the trivalent state of Fe ion. M4,5-edges of La corroborate the +3 state of La in the system. Atomic multiplet calculations are also performed on Fe L3,2-, Mn L3,2- and La M4,5-edges to further verify the valency, symmetry and the crystal field splitting.

We have deposited epitaxial thin films of LaNiO3 (LNO) on LaAlO3 (001) single crystals by rf-magnetron sputtering. Further, we studied the effect of systematically varied swift heavy ion irradiation induced strain on structural, electrical, and magnetotransport properties of the films. Deposited films were irradiated at varying fluence (1×1011, 1×1012, and 5×1012 ions/cm2) using 200 MeV Ag15+ beam. X-ray diffraction results reveal c-axis oriented epitaxial growth of the LNO film which is maintained even up to the highest fluence. All the films, except the one irradiated with highest fluence, show metallic behavior along with a resistivity upturn at lower temperatures. Film irradiated with the highest fluence value exhibits semiconducting behavior in the studied temperature range. Low temperature resistivity of the metallic films has been explained by quantum corrections to conductivity and it is observed that localization increases with the disorder. Presence of weak localization in metallic films is also supported by our magnetotransport data. At high temperatures, variable range hopping shown by the film irradiated with the highest fluence confirms the semiconducting behavior, which may be due to the disorder induced localization of charge carriers.

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We present here the structural, electrical, magnetic and magneto-electric properties of