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arXiv · 2201.07758

Simulating chiral spin liquids with projected entangled-pair states

Juraj Hasik·Maarten Van Damme·Didier Poilblanc·Laurens Vanderstraeten
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Abstract

Doubts have been raised on the representation of chiral spin liquids exhibiting topological order in terms of projected entangled pair states (PEPSs). Here, starting from a simple spin-1/2 chiral frustrated Heisenberg model, we show that a faithful representation of the chiral spin liquid phase is in fact possible in terms of a generic PEPS upon variational optimization. We find a perfectly chiral gapless edge mode and a rapid decay of correlation functions at short distances consistent with a bulk gap, concomitant with a gossamer long-range tail originating from a PEPS bulk-edge correspondence. For increasing bond dimension, (i) the rapid decrease of spurious features -- SU(2) symmetry breaking and long-range tails in correlations -- together with (ii) a faster convergence of the ground state energy as compared to state-of-the-art cylinder matrix-product state simulations involving far more variational parameters, prove the fundamental relevance of the PEPS ansatz for simulating systems with chiral topological order.

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Juraj Hasik, Maarten Van Damme, Didier Poilblanc, Laurens Vanderstraeten. 2022-01-19. Simulating chiral spin liquids with projected entangled-pair states. https://doi.org/10.1103/physrevlett.129.177201

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