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arXiv · 0904.4861

How long can a quantum memory withstand depolarizing noise?

Fernando Pastawski·Alastair Kay·Norbert Schuch·Ignacio Cirac
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Abstract

We investigate the possibilities and limitations of passive Hamiltonian protection of a quantum memory against depolarizing noise. Without protection, the lifetime of a single qubit is independent of N, the number of qubits composing the memory. In the presence of a protecting Hamiltonian, the lifetime increases at most logarithmically with N. We construct an explicit time-independent Hamiltonian which saturates this bound, exploiting the noise itself to achieve the protection.

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Fernando Pastawski, Alastair Kay, Norbert Schuch, Ignacio Cirac. 2009-09-21. How long can a quantum memory withstand depolarizing noise?. https://doi.org/10.1103/physrevlett.103.080501

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