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arXiv · 1406.6926

Blume-Capel model on cylindrical Ising nanowire with core/shell structure: Existence of a dynamic compensation temperatures

Abstract

We present a study, within a mean-field approach, of the kinetics of the spin-1 Blume-Capel model on cylindrical Ising nanowire in the presence of a time-dependent oscillating external magnetic field. We employ the Glauber transition rates to construct the mean-field dynamical equations. We investigate the thermal behavior of the dynamic order parameters. From these studies, we obtain the dynamic phase transition (DPT) points. Then, we study the temperature dependence of the dynamic total magnetization to find the dynamic compensation points as well as to determine the type of behavior. We also investigate the effect of a crystal-field interaction and the exchange couplings between the nearest-neighbor pairs of spins on the compensation phenomenon and construct the phase diagrams in four different planes. The dynamic phase diagrams contain paramagnetic (P), ferromagnetic (F), the antiferromagnetic (AF), and two coexistence or mixed phase regions, namely, the F + P and AF + P that strongly depend on interaction parameters. The system also exhibits the compensation temperatures, or the N-, P-, Q-, S- type behaviors. Furthermore, we also observed two compensation temperatures, namely W-type behaviors, which this result is compared with some experimental works and a good overall agreement is found.

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BibTeXRIS

Mehmet Ertas, Ersin Kantar. 2014-06-26. Blume-Capel model on cylindrical Ising nanowire with core/shell structure: Existence of a dynamic compensation temperatures. https://arxiv.org/abs/1406.6926

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