Optimisation of giant magnetoresistance in Mn-substituted BiFeO3 for low field sensors.

Multiferroicity in perovskite-based ceramics is considered as a foundation of spintronics. Co-existence of two or more ferroic orders in single phase ceramics can be proclaimed as a redeemer for the energy related issues and key element in sensitive device applications. In this work, we report an appropriate magnetoresistive effect for the novel applications in sensing and recording under low magnetic field in BiFe 1-x Mn x O 3 with x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0, synthesised by sol-gel method. All the calcined samples exhibited crystalline texture; however, a gradual structural phase transition was evident with Mn-substitution at Fe-site in BiFeO 3 . The structural analysis revealed that the composition, BiFe .8 Mn .2 O 3 settles with the most stable rhombohedral crystal structure. A giant magnetoresistance effect under an applied magnetic field (up to 6 kOe) has been exhibited by this particular composition attributed to its stable rhombohedral structure. Complex impedance analysis depicted a wide range of applicable frequency suitable for sensing devices at room temperature. The impedance analysis and optimised magnetoresistive effects in Mn-substituted BiFeO 3 could help information technology by rectifying various issues relevant to sensing devices and energy losses in spintronics-based applications at room temperature. [ABSTRACT FROM AUTHOR]