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arXiv · 1209.1265

Measurement-Based Quantum Computation on Symmetry Breaking Thermal States

Keisuke Fujii·Yoshifumi Nakata·Masayuki Ohzeki·Mio Murao
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Abstract

We consider measurement-based quantum computation (MBQC) on thermal states of the interacting cluster Hamiltonian containing interactions between the cluster stabilizers that undergoes thermal phase transitions. We show that the long-range order of the symmetry breaking thermal states below a critical temperature drastically enhance the robustness of MBQC against thermal excitations. Specifically, we show the enhancement in two-dimensional cases and prove that MBQC is topologically protected below the critical temperature in three-dimensional cases. The interacting cluster Hamiltonian allows us to perform MBQC even at a temperature an order of magnitude higher than that of the free cluster Hamiltonian.

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Keisuke Fujii, Yoshifumi Nakata, Masayuki Ohzeki, Mio Murao. 2012-09-06. Measurement-Based Quantum Computation on Symmetry Breaking Thermal States. https://doi.org/10.1103/physrevlett.110.120502

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