title: Coulomb Liquid Phases of Bosonic Cluster Mott Insulators on a Pyrochlore Lattice.
abstract: Employing large-scale quantum Monte Carlo simulations, we reveal the full phase diagram of the extended Hubbard model of hard-core bosons on the pyrochlore lattice with partial fillings. When the intersite repulsion is dominant, the system is in a cluster Mott insulator phase with an integer number of bosons localized inside the tetrahedral units of the pyrochlore lattice. We show that the full phase diagram contains three cluster Mott insulator phases with 1/4, 1/2, and 3/4 boson fillings, respectively. We further demonstrate that all three cluster Mott insulators are Coulomb liquid phases and its low-energy property is described by the emergent compact U(1) quantum electrodynamics. In addition to measuring the specific heat and entropy of the cluster Mott insulators, we investigate the correlation function of the emergent electric field and verify it is consistent with the compact U(1) quantum electrodynamics description. Our result sheds light on the magnetic properties of various pyrochlore systems, as well as the charge physics of the cluster magnets.
authors.affiliation: Department of Physics, Anhui Normal University, Wuhu 241000, China.
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Lv
authors.affiliation: Collaborative Innovation Center of Advanced Microstructures and Department of Physics and Center for Field Theory and Particle Physics, Fudan University, Shanghai 200433, China.|Department of Physics, University of Toronto, Toronto, Ontario M5S1A7, Canada.
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.affiliation: Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei 230027, China.
authors.forename: Youjin
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Zi Yang
authors.initials: ZY
authors.lastname: Meng