2015/11/30 by O. Viyuela, D. Vodola, G. Pupillo +1 · 2 citations
Physics and Astronomy · #cond-mat.str-el #cond-mat.supr-con #quant-ph
paper · pdf · doi:10.1103/physrevb.94.125121
published as Phys. Rev. B 94, 125121 (2016) · RevTex4 file, color figures, close to published version
arxiv created 2016/09/19 · arxiv updated 2016/09/20
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.