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A Majorana Fermion t-J Model in One Dimension

Diptiman Sen·B. Sriram Shastry
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Abstract

We study a rotation invariant Majorana fermion model in one dimension using diagrammatic perturbation theory and numerical diagonalization of small systems. The model is inspired by a Majorana representation of the antiferromagnetic spin-1/2 chain, and it is similar in form to the t-J model of electrons, except that the Majorana fermions carry spin-1 and Z_2 charge. We discuss the implications of our results for the low-energy excitations of the spin-1/2 chain. We also discuss a generalization of our model from 3 species of Majorana fermions to N species; the SO(4) symmetric model is particularly interesting.

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Diptiman Sen, B. Sriram Shastry. 1997-07-07. A Majorana Fermion t-J Model in One Dimension. https://doi.org/10.1088/0953-8984%2F9%2F38%2F005

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