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arXiv · 1601.07073

Manipulation of Majorana states in X-junction geometries

D. N. Aristov·D. B. Gutman
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Abstract

We study quantum manipulation based on four Majorana bound states in X-junction geometry. The parameter space of this setup is bigger than of the previously studied Y-junction and is described by SO(4) symmetry group. In order for quantum computation to be dephasing free, two Majorana states have to stay degenerate at all times. We find a condition necessary for that and compute the Berry's phase, $2α$, accumulated during the manipulation. We construct simple protocols for the variety of values of $α$, including $π/8$ needed for the purposes of quantum computation. Although the manipulations in general X-junction geometry are not topologically protected, they may prove to be a feasible compromise for aims of quantum computation.

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D. N. Aristov, D. B. Gutman. 2016-11-04. Manipulation of Majorana states in X-junction geometries. https://doi.org/10.1088/1751-8113%2F49%2F31%2F315301

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