International Journal of Physics
ISSN (Print): 2333-4568 ISSN (Online): 2333-4576 Website: Editor-in-chief: B.D. Indu
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International Journal of Physics. 2019, 7(1), 6-15
DOI: 10.12691/ijp-7-1-2
Open AccessArticle

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

Kunle Adegoke1, Henry Otobrise2, Tolulope Famoroti1, Adenike Olatinwo1, , Funmi Akintujoye1 and Afees Tiamiyu1

1Department of Physics and Engineering Physics, Obafemi Awolowo University, 220005 Ile-Ife, Nigeria

2Department of Basic Sciences, Lead City University, Ibadan, Nigeria

Pub. Date: January 18, 2019

Cite this paper:
Kunle Adegoke, Henry Otobrise, Tolulope Famoroti, Adenike Olatinwo, Funmi Akintujoye and Afees Tiamiyu. Explicit Matrix Representation for the Hamiltonian of the One Dimensional Spin 1/2 Ising Model in Mutually Orthogonal External Magnetic Fields. International Journal of Physics. 2019; 7(1):6-15. doi: 10.12691/ijp-7-1-2


We derive 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.

ising model quantum fluctuations is non-degenerate non-degenerate rayleigh-schrödinger perturbation theory

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