Robust two-qubit quantum registers

I. A. Grigorenko; D. V. Khveshchenko

doi:10.1103/physrevlett.94.040506

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arXiv · cond-mat/0312349

Robust two-qubit quantum registers

I. A. Grigorenko·D. V. Khveshchenko

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Abstract

We carry out a systematic analysis of a pair of coupled qubits, each of which is subject to its own dissipative environment, and argue that a combination of the inter-qubit couplings which provides for the lowest possible decoherence rates corresponds to the incidence of a double spectral degeneracy in the two-qubit system. We support this general argument by the results of of an evolutionary genetic algorithm which can also be used for optimizing time-dependent processes (gates) and their sequences that implement various quantum computing protocols.

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I. A. Grigorenko, D. V. Khveshchenko. 2004-12-29. Robust two-qubit quantum registers. https://doi.org/10.1103/physrevlett.94.040506

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