2013/11/25 by H. Singh, Harkirat Singh, Singh, H. +19
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Multiferroics and related materials #Photonic Crystals and Applications #Strongly Correlated Electrons (cond-mat.str-el) #Theoretical and Computational Physics #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.1311.6269
6 figures
arxiv created 2013/11/25 · openalex publication_date 2013/11/25 · arxiv updated 2013/11/26 · openalex created_date 2019/06/27 · openalex updated_date 2026/07/28
In this report, the magnetic behaviour of NiCr2O4 bulk and nanoparticle samples under different applied magnetic field has been investigated extensively. Nanoparticles of NiCr2O4 were obtained by mechanical milling of polycrystalline powder prepared by polyol method. FC-ZFC measurement of bulk at different applied magnetic field has revealed the existence of a ferrimagnetic transition around 66K followed by an antiferromagnetic transition close to 30K. However, its nano counterpart has shown remarkable change in magnetic properties - a suppression of ferrimagnetic transition accompanied by strengthening low temperature magnetic phase and observation of a new transition at 90K (TP), which is weakly magnetic in nature. The frequency dependent ac susceptibility data of nanoparticle have been fitted to the well known de Almedia-Thouless equation and a H2/3 dependence of the low temperature peak is observed with a resulting zero field freezing temperature (Tf0) equal to 10.1K. Further, the dynamical behaviour near freezing temperature has been analysed in terms of critical behaviour and the obtained fitted parameters values being as τ0(relaxation time constant) = 3.6 X 10-6s, Tf0=8.7K and zν= 11.1. Moreover, Vogel-Fulcher law has been used to understand the nature of freezing transition and the parameter after fitting are obtained as Ea/kB = 58.9K, τ0 = 5.22 × 10-8 and T0 = 8.03K. Finally, the spin-glass phase is concluded. Moreover, in contrast to bulk, the H2/3 dependence of freezing temperature of nanoparticle sample (75h) does support the 2D surface like spin glass nature.