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arXiv · 1504.04230

Localized Majorana-like modes in a number conserving setting: An exactly solvable model

Fernando Iemini·Leonardo Mazza·Davide Rossini·Rosario Fazio·Sebastian Diehl
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Abstract

In this letter we present, in a number conserving framework, a model of interacting fermions in a two-wire geometry supporting non-local zero-energy Majorana-like edge excitations. The model has an exactly solvable line, on varying the density of fermions, described by a topologically non-trivial ground state wave-function. Away from the exactly solvable line we study the system by means of the numerical density matrix renormalization group. We characterize its topological properties through the explicit calculation of a degenerate entanglement spectrum and of the braiding operators which are exponentially localized at the edges. Furthermore, we establish the presence of a gap in its single particle spectrum while the Hamiltonian is gapless, and compute the correlations between the edge modes as well as the superfluid correlations. The topological phase covers a sizeable portion of the phase diagram, the solvable line being one of its boundaries.

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Fernando Iemini, Leonardo Mazza, Davide Rossini, Rosario Fazio, Sebastian Diehl. 2015-07-31. Localized Majorana-like modes in a number conserving setting: An exactly solvable model. https://doi.org/10.1103/physrevlett.115.156402

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