中国物理B ›› 2018, Vol. 27 ›› Issue (1): 10204-010204.doi: 10.1088/1674-1056/27/1/010204

• GENERAL • 上一篇    下一篇

Quantum Monte Carlo study of hard-core bosons in Creutz ladder with zero flux

Yang Lin(林洋), Weichang Hao(郝维昌), Huaiming Guo(郭怀明)   

  1. Department of Physics, Key Laboratory of Micro-Nano Measurement-Manipulation and Physics(Ministry of Education), Beihang University, Beijing 100191, China
  • 收稿日期:2017-04-13 修回日期:2017-09-12 出版日期:2018-01-05 发布日期:2018-01-05
  • 通讯作者: Huaiming Guo E-mail:hmguo@buaa.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11274032, 11774019, 51472016, and 51672018).

Quantum Monte Carlo study of hard-core bosons in Creutz ladder with zero flux

Yang Lin(林洋), Weichang Hao(郝维昌), Huaiming Guo(郭怀明)   

  1. Department of Physics, Key Laboratory of Micro-Nano Measurement-Manipulation and Physics(Ministry of Education), Beihang University, Beijing 100191, China
  • Received:2017-04-13 Revised:2017-09-12 Online:2018-01-05 Published:2018-01-05
  • Contact: Huaiming Guo E-mail:hmguo@buaa.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11274032, 11774019, 51472016, and 51672018).

摘要: The quantum phase of hard-core bosons in Creutz ladder with zero flux is studied. For a specific regime of the parameters (tx=tp, ty<0), the exact ground-state is found analytically, which is a dimerized insulator with one electron bound in each rung of the ladder. For the case tx,ty,tp>0, the system is exactly studied using quantum Monte Carlo (QMC) method without a sign problem. It is found that the system is a Mott insulator for small tp and a quantum phase transition to a superfluid phase is driven by increasing tp. The critical tpc is determined precisely by a scaling analysis. Since it is possible that the Creutz ladder is realized experimentally, the theoretical results are interesting to the cold-atom experiments.

关键词: quantum Monte Carlo method, Creutz ladder, Mott insulator

Abstract: The quantum phase of hard-core bosons in Creutz ladder with zero flux is studied. For a specific regime of the parameters (tx=tp, ty<0), the exact ground-state is found analytically, which is a dimerized insulator with one electron bound in each rung of the ladder. For the case tx,ty,tp>0, the system is exactly studied using quantum Monte Carlo (QMC) method without a sign problem. It is found that the system is a Mott insulator for small tp and a quantum phase transition to a superfluid phase is driven by increasing tp. The critical tpc is determined precisely by a scaling analysis. Since it is possible that the Creutz ladder is realized experimentally, the theoretical results are interesting to the cold-atom experiments.

Key words: quantum Monte Carlo method, Creutz ladder, Mott insulator

中图分类号:  (Quantum Monte Carlo methods)

  • 02.70.Ss
05.30.Rt (Quantum phase transitions)