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Decoherence-Free Quantum Memory Using Trapped Ions



D Kielpinski, V Meyer, M A. Rowe, C A. Sackett, Wayne M. Itano, C Monroe, David J. Wineland


We demonstrate a decoherence-free quantum memory of one qubit. By encoding the qubit into the decoherence-free subspace (DFS) of a pair of trapped 9Be+ ions, we protect the qubit from environment-induced dephasing that limits the storage time of a qubit composed of a single ion. We measured the storage time under ambient conditions and under interaction with an engineered noisy environment and observed that encoding into the DFS increases the storage time by up to an order of magnitude. The encoding reversibly transfers an arbitrary qubit stored in a single ion to the DFS of two ions.


Kielpinski, D. , Meyer, V. , Rowe, M. , Sackett, C. , Itano, W. , Monroe, C. and Wineland, D. (2001), Decoherence-Free Quantum Memory Using Trapped Ions, Science, [online], (Accessed April 23, 2024)
Created January 1, 2001, Updated February 17, 2017