Topological Equivalence between the Fibonacci Quasicrystal and the Harper Model


  Yaacov Kraus  ,  Oded Zilberberg  ,  Mor Verbin  ,  Yoav Lahini  ,  Yaron Silberberg  
Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel.
Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel.
Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel.
Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel.

Quasicrystals have recently been found to be topologically nontrivial in one-dimension. In particular, the Harper (or Aubry-Andre) model was found to be associated with Chern numbers and topological boundary states. We will show that the Fibonacci quasicrystal, as well as any Fibonacci-like quasicrystal, is topologically equivalent to the Harper model, since they can be extended to equivalent quantum Hall systems [1]. This equivalence is verified experimentally through the absence of a phase transition when deforming between them [2].

 

[1] Phys. Rev. Lett. 109, 116404 (2012)

[2] arXiv:1211.4476