We analyze a Higgs transition from a U(1) Dirac spin liquid to a gapless ℤ_{2}spin liquid. This ℤ_{2}spin liquid is of relevance to the spin
We describe the confining instabilities of a proposed quantum spin liquid underlying the pseudogap metal state of the holedoped cuprates. The spin liquid can be described by a SU(2) gauge theory of
 Award ID(s):
 2002850
 NSFPAR ID:
 10482021
 Publisher / Repository:
 National Academy of Science
 Date Published:
 Journal Name:
 Proceedings of the National Academy of Sciences
 Volume:
 120
 Issue:
 21
 ISSN:
 00278424
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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A<sc>bstract</sc> S = 1/ 2 square lattice antiferromagnet, where recent numerical studies have given evidence for such a phase existing in the regime of high frustration between nearest neighbor and nextnearest neighbor antiferromagnetic interactions (theJ _{1}J _{2}model), appearing in a parameter regime between the vanishing of Néel order and the onset of valence bond solid ordering. The proximate Dirac spin liquid is unstable to monopole proliferation on the square lattice, ultimately leading to Néel or valence bond solid ordering. As such, we conjecture that this Higgs transition describes the critical theory separating the gapless ℤ_{2}spin liquid of theJ _{1}J _{2}model from one of the two proximate ordered phases. The transition into the other ordered phase can be described in a unified manner via a transition into an unstable SU(2) spin liquid, which we have analyzed in prior work. By studying the deconfined critical theory separating the U(1) Dirac spin liquid from the gapless ℤ_{2}spin liquid in a 1/N _{f}expansion, withN _{f}proportional to the number of fermions, we find a stable fixed point with an anisotropic spinon dispersion and a dynamical critical exponentz ≠ 1. We analyze the consequences of this anisotropic dispersion by calculating the angular profiles of the equaltime Néel and valence bond solid correlation functions, and we find them to be distinct. We also note the influence of the anisotropy on the scaling dimension of monopoles. 
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Published by the American Physical Society 2024 
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