Study Of Structural, Transport And Magneto-Crystalline Anisotropy In La1-Xsrxmno3 (0.30 <= X <= 0.40) Perovskite Manganites

In this paper we present structural, transport, magnetic and magneto-crystalline anisotropy of La1-xSrxMnO3 (? = 0.30, 0.33, 0.36, and 0.40) synthesized using the solid-state reaction method. The X-ray diffraction pattern of the samples is well indexed to the rhombohedral structure with R (3) over barc space group. Lattice parameters and unit cell volume are found to decrease monotonically upon increasing Sr2+ concentration at La3+ site. X-ray photoelectron spectroscopy confirms the presence of Mn4+ and Mn3+, the ratio of which (Mn4+/Mn3+) increases from 0.44 to 0.64 with increasing Sr2+ concentration. From the rho(T) and M(T) data analysis, we find that T-MI and M-S are larger for x = 0.33 composition, suggesting a weakening of the double-exchange interaction due to competing super-exchange interactions in x = 0.30, 0.36 and 0.40 samples. We calculated MCA constant (K-1) by fitting the saturation magnetisation data at a higher magnetic field using the law of approach model, M = M-S [1-a/H-b/H-2]-chi H with K-1(2) = (105/8)bMs(2) and is in the order of 10(5) erg/cm(3).