## SciPost Submission Page

# Extended Coulomb liquid of paired hardcore boson model on a pyrochlore lattice

### by Chun-Jiong Huang, Changle Liu, Ziyang Meng, Yue Yu, Youjin Deng, and Gang Chen

### Submission summary

As Contributors: | Gang Chen |

Preprint link: | scipost_201908_00004v1 |

Date submitted: | 2019-08-04 |

Submitted by: | Chen, Gang |

Submitted to: | SciPost Physics |

Domain(s): | Theor. & Comp. |

Subject area: | Condensed Matter Physics - Theory |

### Abstract

There is a growing interest in the U(1) Coulomb liquid in both quantum materials in pyrochlore ice and cluster Mott insulators and cold atom systems. We explore a paired hardcore boson model on a pyrochlore lattice. This model is equivalent to the XYZ spin model that was proposed for rare-earth pyrochlores with “dipole-octupole” doublets. Since our model has no sign problem for quantum Monte Carlo (QMC) simulations in a large parameter regime, we carry out both analytical and QMC calculations. We find that the U (1) Coulomb liquid is quite stable and spans a rather large portion of the phase diagram with boson pairing. Moreover, we numerically find a thermodynamic evidence that the boson pairing could induce a possible Z2 liquid in the vicinity of the phase boundary between Coulomb liquid and Z2 symmetry-broken phase. Besides the materials’ relevance with quantum spin ice, we point to quantum simulation with cold atoms on optical lattices.