Elaboration of Low Field and Room Temperature Magnetoresistive Sensor of La_(0.7)Sr_(0.3)MnO_3 Nanoparticles Synthesized by Sol-Gel Method

摘要

Low field and room temperature operation range are two critical requirements for magnetic sensors. In this paper, nanoparticles of La_(0.7)Sr_(0.3)MnO_3 (LSMO) were elaborated to fulfill these requirements. La_(0.7)Sr_(0.3)MnO_3 nanoparticles were synthesized using sol-gel method. 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 ±110mT. 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 and response time were also given.