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arXiv · 2204.06146

Multi-critical point and unified description of broken-symmetry phases in spin-1/2 anti-ferromagnets on a square lattice

Oğuz Türker·Kun Yang
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Abstract

We show that several distinct broken-symmetry phases in a spin-1/2 anti-ferromagnet on a square lattice with easy-plane anisotropy, including valence bond solid, chiral spin liquid, and the XY-ordered state, can all be accessed by perturbing a multi-critical point with two massless Dirac fermions coupled to a level-one Chern-Simons gauge field. This allows for a unified description of these phases, as well as the phase transitions between them. In a specific phase transition our analysis provide a lattice realization of one of the recently proposed fermion-boson duality, thus lending support to it. We also briefly discuss the relation between our work and the long-sought de-confined criticality in such systems.

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Oğuz Türker, Kun Yang. 2022-04-13. Multi-critical point and unified description of broken-symmetry phases in spin-1/2 anti-ferromagnets on a square lattice. https://doi.org/10.1103/physrevb.105.155150

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