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arXiv · 1102.5153

Thermal States as Universal Resources for Quantum Computation with Always-on Interactions

Ying Li·Daniel E. Browne·Leong Chuan Kwek·Robert Raussendorf·Tzu-Chieh Wei
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Abstract

Measurement-based quantum computation utilizes an initial entangled resource state and proceeds with subsequent single-qubit measurements. It is implicitly assumed that the interactions between qubits can be switched off so that the dynamics of the measured qubits do not affect the computation. By proposing a model spin Hamiltonian, we demonstrate that measurement-based quantum computation can be achieved on a thermal state with always-on interactions. Moreover, computational errors induced by thermal fluctuations can be corrected and thus the computation can be executed fault-tolerantly if the temperature is below a threshold value.

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Ying Li, Daniel E. Browne, Leong Chuan Kwek, Robert Raussendorf, Tzu-Chieh Wei. 2011-08-05. Thermal States as Universal Resources for Quantum Computation with Always-on Interactions. https://doi.org/10.1103/physrevlett.107.060501

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