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arXiv · 1501.04112

Can long-range interactions stabilize quantum memory at nonzero temperature?

Olivier Landon-Cardinal·Beni Yoshida·David Poulin·John Preskill
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Abstract

A two-dimensional topologically ordered quantum memory is well protected against error if the energy gap is large compared to the temperature, but this protection does not improve as the system size increases. We review and critique some recent proposals for improving the memory time by introducing long-range interactions among anyons, noting that instability with respect to small local perturbations of the Hamiltonian is a generic problem for such proposals. We also discuss some broader issues regarding the prospects for scalable quantum memory in two-dimensional systems.

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Olivier Landon-Cardinal, Beni Yoshida, David Poulin, John Preskill. 2015-03-10. Can long-range interactions stabilize quantum memory at nonzero temperature?. https://doi.org/10.1103/physreva.91.032303

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