Entanglement perturbation theory for the elementary excitation in one dimension

Sung Gong Chung; Lihua Wang

doi:10.1016/j.physleta.2009.04.038

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arXiv · 1008.0346

Entanglement perturbation theory for the elementary excitation in one dimension

Sung Gong Chung·Lihua Wang

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Abstract

The entanglement perturbation theory is developed to calculate the excitation spectrum in one dimension. Applied to the spin-$\frac{1}{2}$ antiferromagnetic Heisenberg model, it reproduces the des Cloiseaux-Pearson Bethe ansatz result. As for spin-1, the spin-triplet magnon spectrum has been determined for the first time for the entire Brillouin zone, including the Haldane gap at $k=\pi$.

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Sung Gong Chung, Lihua Wang. 2010-08-02. Entanglement perturbation theory for the elementary excitation in one dimension. https://doi.org/10.1016/j.physleta.2009.04.038

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