2010/01/31 by Anders W. Sandvik · 10 citations
Physics and Astronomy · #Advanced Condensed Matter Physics #Antiferromagnetism #Condensed matter physics #Logarithm #Materials science #Molecule #Phase transition #Physics #Physics of Superconductivity and Magnetism #Quantum #Quantum critical point #Quantum mechanics #Quantum phase transition #Scaling #Theoretical and Computational Physics #Valence (chemistry) #Valence bond theory #cond-mat.str-el #hep-lat
paper · pdf · doi:10.1103/physrevlett.104.177201
published as Phys. Rev. Lett. 104, 177201 (2010) · 4 pages, 5 figures, final published version
openalex publication_date 2010/04/26 · arxiv created 2010/04/29 · arxiv updated 2010/04/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The antiferromagnetic to valence-bond-solid phase transition in the two-dimensional J-Q model (an S=1/2 Heisenberg model with four-spin interactions) is studied using large-scale quantum Monte Carlo simulations. The results support a continuous transition of the ground state, in agreement with the theory of "deconfined" quantum criticality. There are, however, large corrections to scaling, of logarithmic or very slowly decaying power-law form, which had not been anticipated. This suggests that either the SU(N) symmetric noncompact CP;N-1 field theory for deconfined quantum criticality has to be revised or that the theory for N=2 (as in the system studied here) differs significantly from N-->infinity (where the field theory is analytically tractable).