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arXiv · 0711.1365

Anyonic interferometry and protected memories in atomic spin lattices

Liang Jiang·Gavin K. Brennen·Alexey V. Gorshkov·Klemens Hammerer·Mohammad Hafezi·Eugene Demler·Mikhail D. Lukin·Peter Zoller
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Abstract

Strongly correlated quantum systems can exhibit exotic behavior called topological order which is characterized by non-local correlations that depend on the system topology. Such systems can exhibit remarkable phenomena such as quasi-particles with anyonic statistics and have been proposed as candidates for naturally fault-tolerant quantum computation. Despite these remarkable properties, anyons have never been observed in nature directly. Here we describe how to unambiguously detect and characterize such states in recently proposed spin lattice realizations using ultra-cold atoms or molecules trapped in an optical lattice. We propose an experimentally feasible technique to access non-local degrees of freedom by performing global operations on trapped spins mediated by an optical cavity mode. We show how to reliably read and write topologically protected quantum memory using an atomic or photonic qubit. Furthermore, our technique can be used to probe statistics and dynamics of anyonic excitations.

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Liang Jiang, Gavin K. Brennen, Alexey V. Gorshkov, Klemens Hammerer, Mohammad Hafezi, Eugene Demler, Mikhail D. Lukin, Peter Zoller. 2007-11-08. Anyonic interferometry and protected memories in atomic spin lattices. https://doi.org/10.1038/nphys943

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