Quantitative Treatment of Decoherence
نویسندگان
چکیده
We review several approaches to define and quantify decoherence. We find that a measure based on a norm of deviation of the density matrix is appropriate for quantifying decoherence for quantum registers. For a semiconductor double quantum dot charge qubit, evaluation of this measure is presented. For a general class of decoherence processes, including those occurring in semiconductor qubits, we establish that this measure is additive: It scales linearly with the number of qubits in the quantum register.
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