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A naturally error suppressing quantum memory

Fumiko Yamaguchi·Yoshihisa Yamamoto
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Abstract

We propose a method to construct quantum storage wherein the phase error due to decoherence is naturally suppressed without constant error detection and correction. As an example, we describe a quantum memory made of two physical qubits encoded in the ground state of a two-qubit phase-error detecting code. Such a system can be simulated by introducing a coupling between the two physical qubits. This method is effective for physical systems in which the $T_1$ decay process is negligible but coherence is limited by the $T_2$ decay process. We take trapped ions as a possible example to apply the natural suppression method and show that the $T_2$ decay time due to slow ambient fluctuating fields at the physical qubits can be lengthened as much as $10^4$.

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Fumiko Yamaguchi, Yoshihisa Yamamoto. 2006-03-18. A naturally error suppressing quantum memory. https://arxiv.org/abs/quant-ph/0603159

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