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Lenz-Ising-Onsager problem in an external field as a soluble problem of many fermions

Martin S. Kochman'ski
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Abstract

In this paper a new approach to solving the 2D and 3D Ising models in external magnetic field $H\neq0$ is developed. The general formalism for the approach to the problem is presented on the example of the 2D Ising model in the external magnetic field. The paper presents a new method obtaining the Onsager solution and computations of asymptotic forms of low-temperature free energy for the 2D Ising model in the external magnetic field $(H)$. The free energy in the limiting case of the magnetic field tending to zero $(H\to 0, N,M\to\infty)$ at arbitrary temperature is also considered $(T\neq 0)$.

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BibTeXRIS

Martin S. Kochman'ski. 1997-10-20. Lenz-Ising-Onsager problem in an external field as a soluble problem of many fermions. https://doi.org/10.1103/physreve.56.3831

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