Observation of Griffiths-like phase and its tunability in La2Ni1-xCoxCoxO6 (0 ≤ x ≤ 1) nanoparticles

Temperature and magnetic field dependent magnetic properties of La2Ni1-xCoxMnO6 (0 <= x <= 1) nanoparticles prepared by sol-gel method with average particle size similar to 25-60 nm have been investigated. X-ray diffraction and Raman spectra study have revealed the suppression of structural disorder with the increase of Co content. Magnetic ordering and magnetization properties like, transition temperature (T-C), coercive field (H-C) and spontaneous magnetization (M-S) increases with the Co substitution at the Ni site. The inverse magnetic susceptibility above T-C has shown a broad temperature regime with a downward deviation from the Curie-Weiss law, a characteristic feature of Griffiths-like phase. This temperature regime of magnetic inhomogeneity decreases with the increase of Co content and completely absent for La2CoMnO6. (C) 2016 Elsevier B.V. All rights reserved.