Rajesh Debnath

Magnetically tunable alternating current electrical properties of x La0.7Sr0.3MnO3–(1 − x) ErMnO3 (x = 0.1, 0.3, and 0.5) multiferroic nanocomposite

Detailed magnetically tunable ac electrical properties of x La0.7Sr0.3MnO3 (LSMO)–(1 − x) ErMnO3 (EMO) (x = 0.1, 0.3, and 0.5) multiferroic nanocomposites have been studied at 300 K in presence of varying magnetic field (Happl), applied both in parallel and perpendicular configuration with respect to the measuring electric field. AC electrical properties have exhibited significant variation with Happl for all composites, whereas for parallel configuration of Happl such effect is very feeble for x = 0.3 composite. We have attributed this anisotropic behavior to the demagnetization effect in the sample. In contrast, for x = 0.1 and 0.5 composites, no such anisotropy effect is experimentally evidenced. Impedance and real part of impedance have been found to decrease with Happl at low frequency (f) region. We attribute this observation to the depinning of the magnetic domain walls from the grain boundaries pinning centers and thereby enhancing the spin dependent transport in the composite. For x = 0.3 composi...

Magnetoelectric coupling and AC impedance studies of 0.5NiFe2O4-0.5PbZr0.58Ti0.42O3 nanocomposite

We have investigated strain mediated magnetoelectric coupling and ac impedance properties of 0.5NiFe2O4-0.5PbZr0.58Ti0.42O3 nanocomposite at room temperature. The magnetoelectric voltage coefficient has been calculated from ME voltage for both transverse and longitudinal direction at a frequency of 37 Hz. The magnetoelectric coefficient in transverse direction is found to ∼ 2.2 mV/cmOe at 200 Oe dc magnetic field whereas magnetoelectric coefficient in longitudinal direction is found to ∼ 1.36 mV/cmOe at dc magnetic field of 674 Oe. The real and imaginary part of complex impedance has been measured in presence of 0 and 1800 Oe dc magnetic field applied at perpendicular direction of measured electric field. With the application of dc magnetic field slight increase in the real and imaginary part of impedance have been observed. Nyquist plots have been fitted using parallel combinations of resistances-capacitance circuits.