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arXiv · 2202.09279

The Haldane gap in the SU(3) [3 0 0] Heisenberg chain

Lukas Devos·Laurens Vanderstraeten·Frank Verstraete
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Abstract

We calculate the Haldane gap of the $\mathrm{SU}(3)$ spin $[3~0~0]$ Heisenberg model using variational uniform fully symmetric $\mathrm{SU}(3)$ matrix product states, and find that the minimal gap $\Delta /J = 0.0263 $ is obtained in the $[2~1~0]$ sector at momentum $2\pi/3$. We also discuss the symmetry protected topological order of the ground state, and determine the full dispersion relation of the elementary excitations and the correlation lengths of the system.

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Lukas Devos, Laurens Vanderstraeten, Frank Verstraete. 2022-02-18. The Haldane gap in the SU(3) [3 0 0] Heisenberg chain. https://doi.org/10.1103/physrevb.106.155103

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