Tuesday, April 30, 2013

1304.7611 (Dong Wang et al.)

Generalized Hofstadter Model: Band Topology Transitions and Fractional
Quantum Hall States

Dong Wang, Zhao Liu, Junpeng Cao, Heng Fan
Lattice models subjected to an external effective magnetic field can form topological nontrivial bands characterized by integer Chern numbers. In this paper, we investigate a generalized Hofstadter model with tunable nearest-neighbor and next nearest-neighbor hopping, and show that the band topology is much richer compared with the conventional Hofstadter model with only the nearest-neighbor hopping. The phase diagram of band Chern numbers are obtained numerically for simple rational flux density and a classification of phases is discussed. The fractional quantum Hall states in both |C|=1 bands and |C|>1 bands are used to reflect the band topology in different phases. When our model reduces to a one-dimensional lattice, the ground states are crucially different from fractional quantum Hall states.
View original: http://arxiv.org/abs/1304.7611

No comments:

Post a Comment