2012/02/29 by H. Bombin, Ruben S. Andrist, Masayuki Ohzeki +2 · 3 citations
Physics and Astronomy · #quant-ph #cond-mat.dis-nn
paper · pdf · doi:10.1103/physrevx.2.021004
published as Phys. Rev. X 2, 021004 (2012) · 10 pages, 6 figures, 1 table - see Physics Viewpoint by D. Gottesman [http://physics.aps.org/articles/v5/50]
arxiv created 2012/04/30 · arxiv updated 2012/05/30
The inevitable presence of decoherence effects in systems suitable for quantum computation necessitates effective error-correction schemes to protect information from noise. We compute the stability of the toric code to depolarization by mapping the quantum problem onto a classical disordered eight-vertex Ising model. By studying the stability of the related ferromagnetic phase both via large-scale Monte Carlo simulations and via the duality method, we are able to demonstrate an increased error threshold of 18.9(3)% when noise correlations are taken into account. Remarkably, this agrees within error bars with the result for a different class of codes-topological color codes-where the mapping yields interesting new types of interacting eight-vertex models.