2018/11/19 by Anzar Ali, Ali, Anzar, Gyaneshwar Sharma +3
Materials Science · #FOS: Physical sciences #Magnetic Properties and Applications #Magnetic and transport properties of perovskites and related materials #Materials Science (cond-mat.mtrl-sci) #Multiferroics and related materials #Strongly Correlated Electrons (cond-mat.str-el)
paper · pdf · doi:10.48550/arxiv.1811.07836
openalex publication_date 2018/11/19 · openalex created_date 2018/11/29 · openalex updated_date 2026/07/28
The spinel NiCr2O4 is known to show a ferrimagnetic transition at Tc = 70~K, and magneto-structural transitions at Ts = 30~K and To = 20~K\@. We present a detailed magnetic and magnetocaloric effect (MCE = -ΔSM(T)) study across these transitions. The -ΔSM(T) shows a positive anomaly at Tc, Ts, and To. In addition to these anomalies, we report a new unreported feature at T ≈ 8.5~K where -ΔSM(T) shows a negative anomaly or the inverse MCE. An Arrot plot of the isothermal magnetization data reveals important information about the nature of the possible phases revealed in -ΔSM(T). We have also made a scaling analysis of the -ΔSM(T) data around these transitions. This analysis suggests that the transition at Tc is a second-order Mean field like transition, the transition at Ts is not second order and is non-mean field like, while the new transition at T = 8.5~K is non-mean field like but is second order in nature. Our study demonstrates that magnetocaloric effect is sensitive to magneto-structural changes in materials and can be used for the identification of new phases and transitions.