Critical and compensation behavior of a mixed spin-5/2 and spin-3/2 Ising antiferromagnetic system in a core/shell nanowire

Abstract

In this work, Monte Carlo simulations based on metropolis algorithm were performed to study the critical and compensation temperatures of a core-shell nanowire with spins [Formula: see text] and [Formula: see text], respectively, considering an Ising antiferromagnetic system. The influence of nearest neighbors exchange interactions and crystal field anisotropy on the critical and compensation behaviors of the system has been analyzed. The effects of the nanowire height in the critical and compensation temperatures were evaluated. The results show that, for a system with given values of exchange interaction constants and crystal field anisotropy, a compensation point only appears if two requirements are satisfied. First, the weight of the core magnetization in the total magnetization must be greater than the weight of the shell magnetization at zero temperature. And second, the exchange constant of shell ions must be greater than a certain value. This value is, at the same time, greater than the exchange constant of core ions. The critical and compensation temperatures are very sensitive to variations in the exchange constant of the shell ions and core ions, respectively, while the crystal field anisotropy affects both temperatures.

Magnetic properties and hysteresis behavior of a ferrimagnetic mixed spin-3/2 and spin-5/2 Ising nanowire

“…Also, it is clear that the critical temperature increases almost linearly with increasing J A /|J AB | . As a comparison, similar phase diagrams have been observed in some Ising nanowires with mixed spins (1/2, 3/2) (Hachem et al , 2018) and (1/2, 1) (Alrajhi et al , 2018).…”

“…In particular, the research on magnetic nanowires has been receiving considerable attention experimentally; the nanowires Fe 3 O 4 , Co–Cu and CdO can be synthesized by diverse techniques, such as a simple metal displacement deposition method (Yang et al , 2011), an electrodeposition method followed by heat-treating processes (Zhang and Zhang, 2009) and a vapor transport process (Kuo and Huang, 2006). Theoretically, several approaches have been used to investigate the magnetic properties of nanowires, namely, effective field theory with correlations (Kaneyoshi, 2017; Kantar, 2018; Kocakaplan and Ertaş, 2015), mean field approximation (Ertaş and Kantar, 2015; Kantar and Keskin, 2016; Mendes et al , 2018a, b; Masrour et al , 2016), recursion relations on the Bethe lattice (Albayrak, 2016), Monte Carlo simulation (MCS) (Hachem et al , 2018; Alrajhi et al , 2018; Wang et al , 2016; Benhouria et al , 2018; Mendes et al , 2019) and self-consistent ab-initio calculations (Masrour et al , 2014).…”

Hysteresis in core/shell nanowire with mixed spin Ising

“…An increase in the values of coercive field is observed, due to T c moves towards the right, as J ss increases. This phenomenon was explained in preliminary works, where it was found that, the increase in the critical temperature should be maintained periodic with the periodic variation of J ss [16]. In Figure 4c, as K v increases, the same behavior as it obseved in figure 5a appears.…”

“…These changes in the values of H c and T c are due to the combination of J ss and J cc . The study of the changes in T c was previously carried out, considering different values for J ss and J cc [16]. In all cases there is a enhancement of H c , which has been evidenced in previous studies conducted in nanowires by means of Monte Carlo simulations [27,9,14].…”

“…The results of this work are focused on analyzing the behavior of the hysteresis loops and coercive field of core/shell nanowires, below and around of the critical temperature and the compensation temperature. In a previous work, the behavior of critical and compensation temperatures of the core-shell nanowires was studied [16], based on this work, the appropriate parameters were chosen for the simulations, where compensation temperature (T comp ) was observed and there was identified a difference between the compensation and the critical points.…”