“School of Physic”

Back to Papers Home
Back to Papers of School of Physic

Paper   IPM / Physic / 17770
School of Physics
  Title:   Breakdown of the correspondence between the real-complex and delocalization-localization transitions in non-Hermitian quasicrystals
  Author(s): 
1.  W. Chen
2.  S. Cheng
3.  J. Lin
4.  R. Asgari
5.  G. Xianlong
  Status:   Published
  Journal: Phys. Rev. B
  Vol.:  106
  Year:  2022
  Pages:   144208
  Supported by:  IPM
  Abstract:
The correspondence between the real-complex transition in energy and delocalization-localization transition is well established in a class of Aubry-André-Harper model with exponential non-Hermitian on-site potentials. In this paper, we study a generalized Aubry-André model with off-diagonal modulation and non-Hermitian on-site potential. We find that, when there exists an incommensurate off-diagonal modulation, the correspondence breaks down, although the extended phase is maintained in a wide parameter range of the strengths of the on-site potential and the off-diagonal hoppings. An additional intermediate phase with a non-Hermitian mobility edge emerges when the off-diagonal hoppings become commensurate. This phase is characterized by the real and complex sections of the energy spectrum corresponding to the extended and localized states. In this case, the aforementioned correspondence reappears due to the recovery of the PT symmetry.

Download TeX format
back to top
scroll left or right