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Decoherence of Anyonic Charge in Interferometry Measurements

Parsa Bonderson·Kirill Shtengel·J. K. Slingerland
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Abstract

We examine interferometric measurements of the topological charge of (non-Abelian) anyons. The target's topological charge is measured from its effect on the interference of probe particles sent through the interferometer. We find that superpositions of distinct anyonic charges a and a' in the target decohere (exponentially in the number of probes particles used) when the probes have nontrivial monodromy with the charges that may be fused with a to give a'.

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Parsa Bonderson, Kirill Shtengel, J. K. Slingerland. 2007-07-31. Decoherence of Anyonic Charge in Interferometry Measurements. https://doi.org/10.1103/physrevlett.98.070401

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