Co-existence of magnetocaloric effect and magnetoresistance in Co substituted La0.67Sr0.33MnO3 at room temperature

Magnetization (M), Magnetocaloric effect (MCE), and Magnetoresistance (MR) in Co substituted La0.67Sr0.33Mn1-xCoxO3 (x = 0.03, 0.05, and 0.1) samples have been investigated. All the studied samples were crystallized into a single phase rhombohedral structure with R (3) over barc space group. The Curie temperature (T-C) is found to decrease with the increase of Co content and for the composition x = 0.1, a cluster glass-like nature is observed. Temperature variation of magnetic entropy change (Delta S-M) shows a positive peak at TC for the composition x = 0.1 with Delta S-M = 3.1 J/kg K and relative cooling power, RCP = 155 J/kg at a magnetic field of 50 kOe. Again, the critical analysis of the paramagnetic to ferromagnetic transition and the scaling behaviour of field dependence of MCE for x = 0.1 composition is also reported. Furthermore, the temperature dependence of electrical resistivity under the magnetic fields up to 50 kOe is reported along with the values of 20% enhancement in MR at room temperature for the Co substituted samples. (C) 2013 AIP Publishing LLC.