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arXiv · 1107.2697

Non-perturbative gadget for topological quantum codes

Samuel A. Ocko·Beni Yoshida
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Abstract

Many-body entangled systems, in particular topologically ordered spin systems proposed as resources for quantum information processing tasks, often involve highly non-local interaction terms. While one may approximate such systems through two-body interactions perturbatively, these approaches have a number of drawbacks in practice. Here, we propose a scheme to simulate many-body spin Hamiltonians with two-body Hamiltonians non-perturbatively. Unlike previous approaches, our Hamiltonians are not only exactly solvable with exact ground state degeneracy, but also support completely localized quasi-particle excitations, which are ideal for quantum information processing tasks. Our construction is limited to simulating the toric code and quantum double models, but generalizations to other non-local spin Hamiltonians may be possible.

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Samuel A. Ocko, Beni Yoshida. 2011-11-03. Non-perturbative gadget for topological quantum codes. https://doi.org/10.1103/physrevlett.107.250502

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