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Topological massive Dirac edge modes and long-range superconducting Hamiltonians

Authors

O. Viyuela, D. Vodola, G. Pupillo, M.A. Martin-Delgado

Journal Paper

https://doi.org/10.1103/PhysRevB.94.125121

Publisher URL

https://www.aps.org/

Publication date

September 2016

We discover novel topological effects in the one-dimensional Kitaev chain modified by long-range Hamiltonian deformations in the hopping and pairing terms. This class of models display symmetry-protected topological order measured by the Berry/Zak phase of the lower band eigenvector and the winding number of the Hamiltonians. For exponentially-decaying hopping amplitudes, the topological sector can be significantly augmented as the penetration length increases, something experimentally achievable. For power-law decaying superconducting pairings, the massless Majorana modes at the edges get paired together into a massive non-local Dirac fermion localised at both edges of the chain: a new topological quasiparticle that we call topological massive Dirac fermion. This topological phase has fractional topological numbers as a consequence of the long-range couplings. Possible applications to current experimental setups and topological quantum computation are also discussed.