CMR in a manganite with 50% of Ti in the Mn sites

SrLaMnTiO6 orthorhombic perovskite has been synthesized by the liquid-mix technique. Structural characterization from X-ray and neutron diffraction shows a random distribution of Mn and Ti atoms. This material shows ferromagnetic ordering with a Tc=380 KTc=380 K which can be interpreted in terms of a FM mode along y  -axis. A M–I transition and a negative MR response of 90% have been detected at 210 K. AC and DC (ZFC and FC) magnetization measurements show an anomaly at low temperatures which has been attributed to effects of pinning of the FM domain walls rather than SG behaviour. Besides this, linear relation between coercitive field and T1/2T1/2 is interpreted considering the existence of magnetic clusters of the same size embedded in a paramagnetic matrix. Finally the magnetocaloric properties of the title material have been studied and a discrete value of ΔSmax=0.19 Jkg−1K−1 at RT has been found.

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