Gapless spin liquid ground state of the spin- 12 J1−J2 Heisenberg model on square lattices

Wen-Yuan Liu, Shaojun Dong, Chao Wang, Yongjian Han, Hong An, Guang-Can Guo, Lixin He
2018 Physical review B  
The spin-1/2 J_1-J_2 Heisenberg model on square lattices are investigated via the finite projected entangled pair states (PEPS) method. Using the recently developed gradient optimization method combining with Monte Carlo sampling techniques, we are able to obtain the ground states energies that are competitive to the best results. The calculations show that there is no Néel order, dimer order and plaquette order in the region of 0.42 ≲ J_2/J_1≲ 0.6, suggesting a single spin liquid phase in the
more » ... ntermediate region. Furthermore, the calculated staggered spin, dimer and plaquette correlation functions all have power law decay behaviours, which provide strong evidences that the intermediate nonmagnetic phase is a single gapless spin liquid state.
doi:10.1103/physrevb.98.241109 fatcat:mzu6jiacxbgnrfplxwqijkatae