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arXiv · 1207.6888

Dynamical formation and manipulation of Majorana fermions in driven quantum wires

E. Perfetto
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Abstract

Controlling the dynamics of Majorana fermions (MF) subject to time-varying driving fields is of fundamental importance for the practical realization of topological quantum computing. In this work we study how it is possible to dynamically generate and maintain the topological phase in one-dimensional superconducting nanowires after the temporal variation of the Hamiltonian parameters. Remarkably we show that for a sudden quench the system can never relax towards a state exhibiting fully developed MF, independently of the initial and final Hamiltonians. Only for sufficiently slow protocols the system behaves adiabatically, and the topological phase can be reached. Finally we address the crucial question of how "adiabatic" a protocol must be in order to manipulate the MF inside the topological phase without deteriorating their Majorana character.

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E. Perfetto. 2012-07-30. Dynamical formation and manipulation of Majorana fermions in driven quantum wires. https://doi.org/10.1103/physrevlett.110.087001

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