Magnetic, magnetoresistance, and magnetodielectric properties of oxygen deficient charge ordered manganite, Pr0.5Ca0.5MnO3-δ

Magnetization, magnetoresistance, and magnetodielectric measurements have been carried out on oxygen deficient charge ordered manganite, Pr0.5Ca0.5MnO3-δ. The low temperature state shows characteristics which are strongly dependent on the oxygen stoichiometry. A disorder driven phase separation in low temperature state is noticed in the magnetization curve, magnetoresistance, and dielectric measurements which are attributed to oxygen deficiency in the compound. Magnetization and magnetoresistance curves at low temperature display melting of charge ordering and appearance of ferromagnetic metallic state above a critical field, ∼35kOe. This melting of charge ordered state is not observed even up to 50 kOe for the specimen which is annealed in oxygen atmosphere. A considerable magnetodielectric (MD) effect is noticed close to room temperature at 280 K which may be useful for technological applications. Strongest MD effect observed in the range 180-200 K, around TN, is found to be uncorrelated with magnetoresistance. The strong MD effect seems to emerge from the high sensitivity of incommensurate state to the external perturbation such as external magnetic field. - Highlights: → Magnetic, magnetoresistive and magnetodielectric properties are investigated. → The low-temperature properties are strongly influenced by oxygen off-stoichiometry. → A disorder driven phase separation is noticed in low temperature state. → Fairly large magnetodielectric response (close to room temperature) is observed. → Considerable magnetodielectric response is not a consequence of magnetoresistance.