Time: 15:00 (UTC/GMT+08:00, Beijing/Shanghai), Nov. 18 (Wedn.), 2020
Online Meeting Room (zoom.com): Click here to join the meeting
Meeting ID: 932 4250 4088
Speaker: Dr. Zheng Yan (HKU)
Among the quantum many-body models that host anyon excitation and topological orders, quantum dimer models (QDM) provide a unique playground for studying the relation between single-anyon and multi-anyon continuum spectra. However, QDM is a prototypical correlated system with local constraints, whose generic solution at different lattice geometry and parameter regimes is still missing due to the lack of controlled methodologies. Here we obtain, via the newly developed sweeping cluster quantum Monte Carlo algorithm, the excitation spectra in different phases of the triangular lattice QDM. Our results reveal the single vison excitations inside the Z2 quantum spin liquid (QSL) and its condensation towards the p12 × p12 valence bond solid (VBS), and demonstrate the translational symmetry fractionalization and emergent O(4) symmetry at the QSL-VBS transition. We find the single vison excitations, whose convolution qualitatively reproduces the dimer spectra, are not free but subject to interaction effects throughout the transition. The nature of the VBS with its O(4) order parameters are unearthed in full scope. Our approach opens the avenue for generic solution of the static and dynamic properties of QDMs and other strict constrained systems.
Invited by Dr. Rui-Zhen Huang