Robustez da fase topológica fracionária ao ruído de fase

Rafael Antunes Ribeiro

Published Mar 13, 2015• 0 citations

Abstract

In 1984, Berry discovered the geometric phase arising from the geometric structure of the quantum state parameter space and has become an important quantity in Quantum Mechanics. The geometric phase carries the geometric and topological properties of the parameter space. Among the various forms of geometric phase manifested is the fractional topological phase (FTF) arising from the polar decomposition of the evolution operator of the quantum state and that carries the dimension of the Hilbert space where the state lives. In this work we demonstrate theoretically that the FTF is robust to phase¿s noise (dephasing) when inserting phase's noise on the experimental proposal "Fractional topological phase on spatially encoded photonic qudits" of Khoury et all (Phys Rev. A, 87: 042 113, 2013) and treating the problem via Kraus¿maps. This fact makes the fractional topological phase a really reliable candidate for the implementation of quantum algorithms on environments having only phase noise.

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