Coulombic liquid phases of bosonic cluster Mott insulators on pyrochlore lattice

Date

Feb 20, 2015

Time

2:00 PM - 3:00 PM

Speaker

Zi Yang Meng

Affiliation

Institute of Physics, Chinese Academy of Sciences

Language

en

Main Topic

Physik

Other Topics

Physik

Host

CMT seminars

Description

Employing large-scale quantum Monte Carlo simulations, we reveal the full phase diagram of hard-core boson model on the pyrochlore lattice with fractional fillings, considering the boson hopping as well as repulsion between nearest neighbour sites. Due to the partial boson filling, the system is in a cluster Mott insulator (Coulombic liquid) phase with bosons localized inside the tetrahedral units of the pyrochlore lattice when the inter-site repulsion is dominant. We show that the full phase diagram contains three Coulombic liquid phases in the Mott regime at 1/4, 1/2 and 3/4 boson fillings, all of which are described by the emergent compact U (1) quantum electrodynamics (QED). Besides measuring the specific heat and entropy of the cluster Mott insulator phases, we further investigate the boson density-density correlation function and find it is consistent with the electric field correlation of the compact U (1) QED. Our results shed lights on magnetic properties of various pyrochlore systems as well as the charge physics of the cluster magnets.

Last modified: Feb 20, 2015, 8:47:41 AM