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arXiv · 1307.0963

Ultrafast quantum random access memory utilizing single Rydberg atoms in a Bose-Einstein condensate

Kelly R. Patton·Uwe R. Fischer
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Abstract

We propose a long-lived and rapidly accessible quantum memory unit, for which the operational Hilbert space is spanned by states involving the two macroscopically occupied hyperfine levels of a miscible binary atomic Bose-Einstein condensate and the Rydberg state of a single atom. It is shown that an arbitrary qubit state, initially prepared using a flux qubit, can be rapidly transferred to and from the trapped atomic ensemble in approximately 10 ns and with a large fidelity of 97%, via an effective two-photon process using an external laser for the transition to the Rydberg level. The achievable ultrafast transfer of quantum information therefore enables a large number of storage and retrieval cycles from the highly controllable quantum optics setup of a dilute ultracold gas, even within the typically very short flux qubit lifetimes of the order of microseconds.

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Kelly R. Patton, Uwe R. Fischer. 2013-12-18. Ultrafast quantum random access memory utilizing single Rydberg atoms in a Bose-Einstein condensate. https://doi.org/10.1103/physrevlett.111.240504

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