Rare-earth tuned magnetism and magnetocaloric effects in double perovskites R2NiMnO6. (16th December 2021)

• Record Type: Journal Article
• Authors: Ali, Anzar; Pasrija, Kanika; Sharma, Gyaneshwar; Kumar, Sanjeev; Singh, Yogesh
• Is Part Of: Journal of physics. Volume 34:Number 9(2022)
• Publication Date: 2021-12-16
• Subjects: magnetocaloric -- double perovskites -- classical Monte Carlo -- magnetism; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/ac3e9e
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: We present a comprehensive experimental study of magnetization (2 < T < 300 K, 1 < H < 8 T) and magnetocaloric effect in double perovskite materials R 2 NiMnO6 with R = Pr, Nd, Sm, Gd, Tb, and Dy. While a paramagnetic to ferromagnetic transition, with TC in the range ∼ 100 − 200 K, is a common feature that can be attributed to the ordering of Mn 4+ and Ni 2+ magnetic moments, qualitatively distinct behavior depending on the choice of R is observed at low temperatures. These low-temperature anomalies in magnetization are also manifest in the change in magnetic entropy, −Δ S M, whose sign depends on the choice of R . In order to understand these results, we present theoretical analysis based on mean-field approximation and Monte Carlo simulations on a minimal spin model. The model correctly captures the key features of the experimental observations.