A thermal expansion study of the magnetoresistive perovskite compound La0.7Ca0.3MnO3

This paper describes thermal expansion studies carried out on the magnetoresistive compound La0.7Ca0.3MnO3 in the temperature range 90K-293K using a three terminal capacitive dilatometer. This perovskite structure compound undergoes a transition from a paramagnetic to a ferromagnetic state at the Curie temperature (Tc) which is also accompanied by a change in the conductivity behaviour from insulating to metallic and shows colossal magnetoresistance below Tc. The measured fractional length change shows a pronounced change at Tc and the linear thermal expansion coefficient (α) shows a peak at Tc