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A<sc>bstract</sc> We study a surface defect in the free and criticalO(N) vector models, defined by adding a quadratic perturbation localized on a two-dimensional subspace of thed-dimensional CFT. We compute the beta function for the corresponding defect renormalization group (RG) flow, and provide evidence that at long distances the system flows to a nontrivial defect conformal field theory (DCFT). We use epsilon and largeNexpansions to compute several physical quantities in the DCFT, finding agreement across different expansion methods. We also compute the defect free energy, and check consistency with the so-calledb-theorem for RG flows on surface defects.
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Line defects in fermionic CFTs
A<sc>bstract</sc> We study line defects in the fermionic CFTs in the Gross-Neveu-Yukawa universality class in dimensions 2< d <4. These CFTs may be described as the IR fixed points of the Gross-Neveu-Yukawa (GNY) model ind= 4 −ϵ, or as the UV fixed points of the Gross-Neveu (GN) model, which can be studied using the largeNexpansion in 2< d <4. These models admit natural line defects obtained by integrating over a line either the scalar field in the GNY description, or the fermion bilinear operator in the GN description. We compute the beta function for the defect RG flow using both the epsilon expansion and the largeNapproach, and find IR stable fixed points for the defect coupling, thus providing evidence for a non-trivial IR DCFT. We also compute some of the DCFT observables at the fixed point, and check that theg-function associated with the circular defect is consistent with theg-theorem for the defect RG flow.
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- Award ID(s):
- 2209997
- PAR ID:
- 10522230
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2023
- Issue:
- 8
- ISSN:
- 1029-8479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1007/JHEP08(2023)224
