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arXiv · 1610.04485

Exact Solution to Interacting Kitaev Chain at Symmetric Point

Jian-Jian Miao·Hui-Ke Jin·Fu-Chun Zhang·Yi Zhou
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Abstract

Kitaev chain model with nearest neighbor interaction U is solved exactly at the symmetry point $Δ=t$ and chemical potential $μ=0$ in open boundary condition. By applying two Jordan-Wigner transformations and a spin-rotation, such a symmetric interacting model is mapped to a non-interacting fermion model, which can be diagonalized exactly. The solutions include topologically non-trivial phase at $|U| t$. The two phases are related by dualities. Quantum phase transitions in the model are studied with the help of the exact solution.

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Jian-Jian Miao, Hui-Ke Jin, Fu-Chun Zhang, Yi Zhou. 2017-03-09. Exact Solution to Interacting Kitaev Chain at Symmetric Point. https://doi.org/10.1103/physrevlett.118.267701

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