Critical states and fractal attractors in fractal tongues: Localization in the Harper map
Abstract
Localized states of Harper's equation correspond to strange nonchaotic attractors (SNAs) in the related Harper mapping. In parameter space, these fractal attractors with nonpositive Lyapunov exponents occur in fractally organized tongue--like regions which emanate from the Cantor set of eigenvalues on the critical line $\epsilon = 1$. A topological invariant characterizes wavefunctions corresponding to energies in the gaps in the spectrum. This permits a unique integer labeling of the gaps and also determines their scaling properties as a function of potential strength.
- Publication:
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Physical Review E
- Pub Date:
- October 2001
- DOI:
- 10.1103/PhysRevE.64.045204
- arXiv:
- arXiv:nlin/0105013
- Bibcode:
- 2001PhRvE..64d5204S
- Keywords:
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- Nonlinear Sciences - Chaotic Dynamics
- E-Print:
- 11 Pages, 5 figures(three eps format and two in gif format)