Chiral Spin Liquid in Frustrated Anisotropic Kagome Antiferromagnetic Model

• 作 者: 陈焱;
• 出 处: 第十三届国际凝聚态理论与计算材料学会议(The 13th International Conference on Con
• 发表日期: 2014年期

　　Kalmeyer-Laughlin (KL) chiral spin liquid (CSL) is a type of quantum spin liquid without time-reversal symmetry, and it is considered as the parent state of an exotic type of superconductor-anyon superconductor.Such an exotic state has been sought for more than twenty years;however, it remains unclear whether it can exist in a realistic system where time-reversal symmetry is breaking spontaneously.By using the density matrix renormalization group, we show that KL CSL exists in a frustrated anisotropic kagome antiferromagnetic model, which has time-reversal symmetry breaking.We find that our model has two topological degenerate ground states, which exhibit nonvanishing scalar chirality order and are protected by finite excitation gap.Furthermore, we identify this state as KL CSL by the characteristic edge conformal field theory from the entanglement spectrum and the quasiparticles braiding statistics extracted from the modular matrix.Also we obtain the time-reversal invariant spin liquid by tuning the interactions, and we show the continuous phase transition betveen two spin liquids.Finally we construct a phenomenological theory and propose that the double-semion spin liquid is the candidate ground state of nearest neighbor XXZ kagome antiferromagnets.