Monopoles in CP(N-1) model via the state-operator correspondence
arXiv:0809.2816 · doi:10.1103/PhysRevB.78.214418
Abstract
One of the earliest proposed phase transitions beyond the Landau-Ginzburg-Wilson paradigm is the quantum critical point separating an antiferromagnet and a valence-bond-solid on a square lattice. The low energy description of this transition is believed to be given by the 2+1 dimensional CP(1) model -- a theory of bosonic spinons coupled to an abelian gauge field. Monopole defects of the gauge field play a prominent role in the physics of this phase transition. In the present paper, we use the state-operator correspondence of conformal field theory in conjunction with the 1/N expansion to study monopole operators at the critical fixed point of the CP(N-1) model. This elegant method reproduces the result for monopole scaling dimension obtained through a direct calculation by Murthy and Sachdev. The technical simplicity of our approach makes it the method of choice when dealing with monopole operators in a conformal field theory.
14 pages, 1 figure
References in corpus (10)
- "Deconfined" quantum critical points
- Quantum criticality beyond the Landau-Ginzburg-Wilson paradigm
- Spin Dynamics of the Spin-1/2 Kagome Lattice Antiferromagnet ZnCu_3(OH)_6Cl_2
- Projected wavefunction study of Spin-1/2 Heisenberg model on the Kagome lattice
- Evidence for deconfined quantum criticality in a two-dimensional Heisenberg model with four-spin interactions
- Quantum magnetism in the paratacamite family: towards an ideal kagome lattice
- U(1) Gauge Theory of the Hubbard Model : Spin Liquid States and Possible Application to k-(BEDT-TTF)_2 Cu_2 (CN)_3
- On the stability of U(1) spin liquids in two dimensions
- Scaling in the Fan of an Unconventional Quantum Critical Point
- Stability of the U(1) spin liquid with spinon Fermi surface in 2+1 dimensions