Abelian and non-abelian symmetries in infinite projected entangled pair states

Claudius Hubig

doi:10.21468/scipostphys.5.5.047

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arXiv · 1808.10804

Abelian and non-abelian symmetries in infinite projected entangled pair states

Claudius Hubig

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Abstract

We explore in detail the implementation of arbitrary abelian and non-abelian symmetries in the setting of infinite projected entangled pair states on the two-dimensional square lattice. We observe a large computational speed-up; easily allowing bond dimensions $D = 10$ in the square lattice Heisenberg model at computational effort comparable to calculations at $D = 6$ without symmetries. We also find that implementing an unbroken symmetry does not negatively affect the representative power of the state and leads to identical or improved ground-state energies. Finally, we point out how to use symmetry implementations to detect spontaneous symmetry breaking.

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Claudius Hubig. 2018-08-31. Abelian and non-abelian symmetries in infinite projected entangled pair states. https://doi.org/10.21468/scipostphys.5.5.047

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