A Spin $1/2$ Fermions Chain with $XY$ Interaction

Gianluca Francica

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arXiv · 2105.04326

A Spin $1/2$ Fermions Chain with $XY$ Interaction

Gianluca Francica

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Abstract

We consider a chain of spinful fermions with nearest neighbor hopping in the presence of a $XY$ antiferromagnetic interaction. The $XY$ term is mapped onto a Kitaev chain at half-filling such that displays a bosonic zero mode topologically protected and long-range order. As the strength of the hopping amplitude is changed, the system undergoes a quantum phase transition from the topological non-trivial to the trivial phase. We apply the finite-size scaling method to determinate the phase diagram of the model.

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Gianluca Francica. 2021-05-10. A Spin $1/2$ Fermions Chain with $XY$ Interaction. https://arxiv.org/abs/2105.04326

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