Many-Body Spin Berry Phases Emerging from the π-Flux State: Competition between Antiferromagnetism and the Valence-Bond-Solid State

摘要: We uncover new topology-related features of the $\ensuremath{\pi}$-flux saddle-point solution $D=2+1$ Heisenberg antiferromagnet. note that symmetries spinons sustain a built-in competition between antiferromagnetic (AFM) and valence-bond-solid (VBS) orders, two tendencies central to recent developments on quantum criticality. An effective theory containing an analogue Wess-Zumino-Witten term is derived, which generates phases related AFM monopoles with VBS cores, reproduces Haldane's hedgehog Berry phases. The readily generalizes states for all $D$.