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ordered ferromagnet. Effects of Depolarization on Topological Qubits Helmut Katzgraber , Texas A&M Research Foundation, DMR 1151387.
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ordered ferromagnet Effects of Depolarization on Topological QubitsHelmut Katzgraber, Texas A&M Research Foundation, DMR 1151387 The inevitable presence of decoherence effects in systems suitable for quantum computation necessitates effective error-correction schemes to protect information from noise. A robust approach to quantum error correction is given via topologically-protected quantum codes. We have computed 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 via large-scale Monte Carlo simulations, 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 topological color codes. Simulated lattice when studying the depolarizing error channel for color codes. Tc pc = 18.9% Nishimori line p Disorder p vs temperature Tc phase diagram to estimate the error threshold pc. • Phys. Rev. X 2, 021004 (2012) • see Physics Viewpoint by D. Gottesman,Physics 5, 50 (2012)
Effects of Depolarization on Topological QubitsHelmut Katzgraber, Texas A&M Research Foundation, DMR 1151387 • Research project highlighted in a Physics Viewpoint [D. Gottesman, Physics 5, 50 (2012)]. • News features: Texas Advanced Computing Center (TACC), HPC Wire, Supercomputing Online, and Texas A&M Science News. • Multiple presentations by the PI, as well as graduate student R. Andrist at different national and international conferences. • Graduate student R. Andrist has been trained in the development of efficient computer codes that can be applied to a variety of systems. • Code will soon be available online under a cite-me license. PI Katzgraber explaining the ‘Physics of Scuba’ demo developed by the group at the Texas A&M Physics Festival.