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arXiv · 0805.3904

Quantum Phase Transition in the One-Dimensional XZ Model

Wojciech Brzezicki·Andrzej M. Oles
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Abstract

We introduce a one-dimensional (1D) XZ model with alternating $\sigma_i^z\sigma_{i+1}^z$ and $\sigma_i^x\sigma_{i+1}^x$ interactions on even/odd bonds, interpolating between the Ising model and the quantum compass model. We present two ways of its exact solution by: ($i$) mapping to the quantum Ising models, and ($ii$) using fermions with spin 1/2. In certain cases the nearest neighbor pseudospin correlations change discontinuously at the quantum phase transition, where one finds highly degenerate ground state of the 1D compass model.

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Wojciech Brzezicki, Andrzej M. Oles. 2008-05-26. Quantum Phase Transition in the One-Dimensional XZ Model. https://doi.org/10.12693/aphyspola.115.162

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