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arXiv · 2411.14114

Dirac and chiral spin liquids on spin-1/2 square-lattice Heisenberg antiferromagnet

Hui-Ke Jin·Hong-Hao Tu·Ya-Hui Zhang
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Abstract

We revisit the challenging problem of identifying the quantum spin liquid candidate in the spin-1/2 $J_1$-$J_2$ Heisenberg antiferromagnet on the square lattice. By integrating the Gutzwiller-guided density matrix renormalization group method with analytical analyses, we present clear evidence that the ground state is a Z$_2$ Dirac spin liquid. This state can be efficiently described by a Gutzwiller-projected parton theory characterized by its projective symmetry group. To distinguish the difference between the projected Z$_2$ and U(1) parton state, we investigate the chiral spin liquid ground states as topological orders by incorporating a $J_\chi$ term into the $J_1$-$J_2$ model and observe a transition from a Z$_2$ chiral spin liquid to a U(1)$_2$ chiral spin liquid as $J_\chi$ increases.

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Hui-Ke Jin, Hong-Hao Tu, Ya-Hui Zhang. 2024-11-21. Dirac and chiral spin liquids on spin-1/2 square-lattice Heisenberg antiferromagnet. https://arxiv.org/abs/2411.14114

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