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arXiv · 2212.04863

Plaquette valence bond state in spin-1/2 J1-J2 XY model on square lattice

Y. -H. Chan·Hong-Chen Jiang·Y. -C. Chen
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Abstract

We studied the ground state phase diagram of spin-1/2 J1-J2 XY model on the square lattice with first- J1 and second-neighbor J2 antiferromagnetic interactions using both iDMRG and DMRG approaches. We show that a plaquette valence bond phase is realized in an intermediate region 0.50 <= J2/J1 <= 0.54 between a N\'eel magnetic ordered phase at J2/J1 < 0.50 and a stripy magnetic ordered phase at J2/J1 >= 0.54. The plaquette valence bond phase is characterized by finite dimer orders in both the horizontal and vertical directions. Contrary to the spin-1/2 J1-J2 Heisenberg model, we do not find numerical evidence for a quantum spin liquid phase in the J1-J2 XY model.

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Y. -H. Chan, Hong-Chen Jiang, Y. -C. Chen. 2022-12-09. Plaquette valence bond state in spin-1/2 J1-J2 XY model on square lattice. https://doi.org/10.1103/physrevb.107.214402

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