Structural and magnetotransport properties of the Si doped B-site in La0.6Gd0.1Sr0.3 Mn1-xSixO3 (0 ≤ x ≤ 0.15) manganite.

The influence of partial substitution of Mn by Si on the structural, magnetic and electrical properties of La 0.6 Gd 0.1 Sr 0.3 Mn 1-x Si x O 3 (0 ≤ x ≤ 0.15) is studied. All compositions were synthesized using the sol-gel technique. X-ray diffraction and structure refinement show that they crystallize in the rhombohedra structure with the R 3 ¯ c space group. The magnetization and electrical measurements versus temperature proved that all samples exhibit a paramagnetic to a ferromagnetic transition and a semi-conductor to a metallic one when the temperature decreases. The substitution of Mn by silicon (Si) leads to a continuous decrease of both the Curie temperature T C (from 350 K for x = 0.0–278 K for x = 0.15) and the resistivity transition temperature T M-Sc (from 325 K for x = 0.0–263 K for x = 0.15). The magnetoresistance (MR) as well as the resistivity are found to increase. [ABSTRACT FROM AUTHOR]