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The International Journal of Physics

Explicit Matrix Representation for the Hamiltonian of the One Dimensional Spin $1/2$ Ising Model in Mutually Orthogonal External Magnetic Fields

Kunle Adegoke, Henry Otobrise, Tolulope Famoroti, Adenike Olatinwo, Afees Tiamiyu, Funmi Akintujoye

Published Aug 1, 2015• 0 citations
Publisher

Abstract

We give an explicit matrix representation for the Hamiltonian of the Ising model in mutually orthogonal external magnetic fields, using as basis the eigenstates of a system of non-interacting spin~$1/2$ particles in external magnetic fields. We subsequently apply our results to obtain an analytical expression for the ground state energy per spin, to the fourth order in the exchange integral, for the Ising model in perpendicular external fields.

DOI
10.12691/ijp-7-1-2

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