Thermodynamic and magnetic properties of the Ising model with nonmagnetic impurities

D. N. Yasinskaya; Yu. D. Panov

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arXiv · 2401.15087

Thermodynamic and magnetic properties of the Ising model with nonmagnetic impurities

D. N. Yasinskaya·Yu. D. Panov

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Abstract

We consider a system of Ising spins s=1/2 with nonmagnetic impurities with charge associated with pseudospin S=1. The charge density is fixed pursuant to the concentration n. Analysis of the thermodynamic properties in the one-dimensional case showed the presence of so-called pseudotransitions at the boundaries between the staggered charge ordering and (anti)ferromagnetic ordering. In the case of n=0, a "1st order" pseudotransition was discovered. This type of pseudotransition is inherent for a series of other one-dimensional frustrated models. However, for n != 0 we discovered a new type of "2nd order" pseudotransition, which had not previously been observed in other systems.

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D. N. Yasinskaya, Yu. D. Panov. 2024-01-20. Thermodynamic and magnetic properties of the Ising model with nonmagnetic impurities. https://arxiv.org/abs/2401.15087

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