Elaboration of Low Field and Room Temperature Magnetoresistive Sensor of La0.7Sr0.3MnO3 Nanoparticles Synthesized by Sol-Gel Method

Abstract

Low field and room temperature operation range are two critical requirements for magnetic sensors. In this paper, nanoparticles of La0.7Sr0.3MnO3 (LSMO) were elaborated to fulfill these requirements. La0.7Sr0.3MnO3 nanoparticles were synthesized using sol-gel method. The physical properties of LSMO were examined by X-Ray diffraction and Scanning Electron Microscope. The ferromagnetic nature of LSMO samples was confirmed by magnetization measurements. Nanoparticles were pressed in shape of pellets and sintered at different temperatures of 900°C, 1000°C, 1100°C and 1200°C. Magnetoresistive measurements were taken at room temperature with magnetic field (μH) in range ±110 mT. The experimental results show maximum magnetoresistive ratio and sensitivity of 1.3% and 0.023%/mT respectively for sample sintered at 1000°C. Other sensor characteristics namely hysteresis error, response time and noise measurement were also given.