中国物理B ›› 2015, Vol. 24 ›› Issue (7): 77101-077101.doi: 10.1088/1674-1056/24/7/077101

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Structure-dependent metal—insulator transition in one-dimensional Hubbard superlattice

张亮亮a, 黄金a, 段丞博b, 王为忠a   

  1. a Department of Physics, Wuhan University, Wuhan 430072, China;
    b College of Science, Chang'an University, Xi'an 710064, China
  • 收稿日期:2014-11-12 修回日期:2015-01-28 出版日期:2015-07-05 发布日期:2015-07-05
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 50573059 and 10874132).

Structure-dependent metal—insulator transition in one-dimensional Hubbard superlattice

Zhang Liang-Liang (张亮亮)a, Huang Jin (黄金)a, Duan Cheng-Bo (段丞博)b, Wang Wei-Zhong (王为忠)a   

  1. a Department of Physics, Wuhan University, Wuhan 430072, China;
    b College of Science, Chang'an University, Xi'an 710064, China
  • Received:2014-11-12 Revised:2015-01-28 Online:2015-07-05 Published:2015-07-05
  • Contact: Zhang Liang-Liang E-mail:dlzhang@whu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 50573059 and 10874132).

摘要: We investigate the charge and spin gaps, and the spin structure in half-filled one-dimensional Hubbard superlattices with one repulsive site and L0 free sites per unit cell. For odd L0, it is correlated metal at the particle–hole symmetric point, and then turns into band insulator beyond this point. For even L0, the system has a Mott insulator phase around the particle–hole symmetric point and undergoes a metal–insulator transition with on-site repulsion U increasing. For large U, there exists a multiperiodic spin structure, which results from the ferromagnetic (antiferromagnetic) correlation between the nearest neighboring repulsive sites for odd (even) L0.

关键词: metal-insulator transition, spin-density-wave, Hubbard superlattice

Abstract: We investigate the charge and spin gaps, and the spin structure in half-filled one-dimensional Hubbard superlattices with one repulsive site and L0 free sites per unit cell. For odd L0, it is correlated metal at the particle–hole symmetric point, and then turns into band insulator beyond this point. For even L0, the system has a Mott insulator phase around the particle–hole symmetric point and undergoes a metal–insulator transition with on-site repulsion U increasing. For large U, there exists a multiperiodic spin structure, which results from the ferromagnetic (antiferromagnetic) correlation between the nearest neighboring repulsive sites for odd (even) L0.

Key words: metal-insulator transition, spin-density-wave, Hubbard superlattice

中图分类号:  (Lattice fermion models (Hubbard model, etc.))

  • 71.10.Fd
71.30.+h (Metal-insulator transitions and other electronic transitions) 73.21.Cd (Superlattices) 75.30.Fv (Spin-density waves)