摘要
We report a quantum Monte Carlo study of the phase transition between antiferromagnetic and valence-bond solid ground states in the square-lattice S=1/2 J-Q model.The critical correlation function of the Q terms gives a scaling dimension corresponding to the value v=0.455±0.002 of the correlation-length exponent.This value agrees with previous(less precise)results from conventional methods,e.g.,finite-size scaling of the nearcritical order parameters.We also study the Q-derivatives of the Binder cumulants of the order parameters for L2 lattices with L up to 448.The slope grows as L1/v with a value of v consistent with the scaling dimension of the Q term.There are no indications of runaway flow to a first-order phase transition.The mutually consistent estimates of v provide compelling support for a continuous deconfined quantum-critical point.
作者
Anders W.Sandvik
Bowen Zhao
Anders W.Sandvik;赵博文(Department of Physics,Boston University,Boston,Massachusetts 02215,USA;Beijing National Laboratory for Condensed Matter Physics and Institute of Physics,Chinese Academy of Sciences,Beijing 100190)
基金
National Science Foundation(USA)under Grant No.DMR-1710170
Simons Foundation under a Simons Investigator Award。
