Effect of Al doping on electronic, magnetic and transport properties of pulsed laser deposited La0.7Ca0.3MnO3 thin films

(La-Ca)MnO3 ortho-perovskites belonging to the class of strongly correlated electron systems are extensively studied over the past few years due to their strong potential for device application. These manganites have very rich phase diagram and one can tune the transport or/and magnetic properties by controlling the composition and varying external conditions such as temperature, magnetic field or pressure. Al, as a dopant at Mn site is particularly attractive because of its non magnetic nature and is preferred among other dopants to study the complex phenomenon taking place in these materials with ease. Doping of Al is expected to alter the Mn-O-Mn network, which controls the magnetic and transport properties. This will lead to reduced ferromagnetic double exchange interaction and also, antiferromagnetic superexchange interaction would become effective. All these factors may result in modified magnetic and transport properties. We prepared La0.7Ca0.3Mn1-xAlxO3 (X= 0, 0.05, 0.15) epitaxial thin films on LaO substrate by pulsed laser deposition technique and studied their magnetic, transport and electronic properties