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arXiv:2403.00597 · Physical review. B./Physical review. B

Chiral spin liquid on a Shastry-Sutherland Heisenberg antiferromagnet

Jian-Wei Yang, Weiwei Luo, W. Zhu, Lihua Wang, Bo Yang, Pinaki Sengupta

Published May 3, 2024• 1 citation
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Abstract

We demonstrate the existence of a topological chiral spin liquid in the frustrated Shastry-Sutherland Heisenberg model with an additional spin chirality interaction, using numerically unbiased exact diagonalization and density matrix renormalization group methods. We establish a quantum phase diagram where conventional phases, including dimer singlet, plaquette singlet, N\'eel, and collinear phase, can be clearly identified by suitable local order parameters. Among them, an $\text{SU}{(2)}_{1}$ chiral spin liquid emerges in the highly frustrated region, which is unambiguously identified by two topologically degenerate ground states, a modular matrix, and characteristic level counting in an entanglement spectrum, featuring the same topological order of the $\ensuremath{\nu}=1/2$ bosonic Laughlin state. The phase boundaries among the different orders are determined by the energy level crossing analysis and wave-function fidelity susceptibility.

DOI
10.1103/physrevb.109.205111

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Evidence for a Z2\mathbb{Z}_{2}Z2​ Dirac spin liquid in the generalized Shastry-Sutherland model
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