Multifunctionality attributed to the self-doping in polycrystalline La0.9MnO3: Coexistence of large magnetoresistance and magnetocaloric effect

We report the multifunctionality near room temperature attributed to the self-doping in polycrystalline La0.9MnO3. The peak in the temperature dependence of magnetoresistance (MR) and change of magnetic entropy (Delta S-M) are observed at 254 K with -MR=55% at 50 kOe and -S-M=4.9 J/kg K at 20 kOe where the Curie temperature and metal-insulator transition coexist at 254 K associated with a first order transition. The correlation between resistivity and Delta S-M is observed in a limited region around T-C. Here Delta S-M is close to the largest reported values in manganites, suggesting that the material is interesting for multiple applications.