Reentrant topological transitions in a quantum wire/superconductor system with quasiperiodic lattice modulation

Masaki Tezuka; Norio Kawakami

doi:10.1103/physrevb.85.140508

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arXiv · 1202.5969

Reentrant topological transitions in a quantum wire/superconductor system with quasiperiodic lattice modulation

Masaki Tezuka·Norio Kawakami

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Abstract

We study the condition for a topological superconductor (TS) phase with end Majorana fermions to appear when a quasiperiodic lattice modulation is applied to a one-dimensional quantum wire with strong spin-orbit interaction situated under a magnetic field and in proximity to a superconductor. By density-matrix renormalization group analysis, we find that multiple topological phases with Majorana end modes are realized in finite ranges of the filling factor, showing a sequence of reentrant transitions as the chemical potential is tuned. The locations of these phases reflect the structure of bands in the non-interacting case, which exhibits a distinct self-similar structure. The stability of the TS in the presence of an on-site interaction or a harmonic trap potential is also discussed.

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Masaki Tezuka, Norio Kawakami. 2012-02-27. Reentrant topological transitions in a quantum wire/superconductor system with quasiperiodic lattice modulation. https://doi.org/10.1103/physrevb.85.140508

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