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arXiv · 1602.07279

Zero temperature non-plateau magnetization and magnetocaloric effect in an Ising-XYZ diamond chain structure

Abstract

Zero temperature non-plateau magnetization is a peculiar property of a quantum spin chain and it sometimes appears due to different gyromagnetic factors. In this study, we illustrate a quite unusual nonplateau magnetization property driven by XY-anisotropy in an Ising-XYZ diamond chain. Two particles with spin-1/2 are bonded by XYZ coupling and they are responsible for the emergence of non-plateau magnetization. These two quantum operator spins are bonded to two nodal Ising spins and this process is repeated infinitely to yield a diamond chain structure. Due to the non-plateau magnetization property, we focus our discussion on the magnetocaloric effect of this model by presenting the isentropic curves and the Gruneisen parameters, as well as showing the regions where the model exhibits an efficient magnetocaloric effect. Due to the existence of two phases located very close to each other, the strong XY-anisotropy exhibits a particular behavior with a magnetocaloric effect, with a wider interval in the magnetic field, where the magnetocaloric effect is efficient.

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J. Torrico, M. Rojas, S. M. de Souza, Onofre Rojas. 2016-09-16. Zero temperature non-plateau magnetization and magnetocaloric effect in an Ising-XYZ diamond chain structure. https://doi.org/10.1016/j.physleta.2016.08.007

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