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arXiv · 0909.5397

Quantum gate in the decoherence-free subspace of trapped ion qubits

Peter A. Ivanov·Ulrich G. Poschinger·Kilian Singer·Ferdinand Schmidt-Kaler
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Abstract

We propose a geometric phase gate in a decoherence-free subspace with trapped ions. The quantum information is encoded in the Zeeman sublevels of the ground-state and two physical qubits to make up one logical qubit with ultra long coherence time. Single- and two-qubit operations together with the transport and splitting of linear ion crystals allow for a robust and decoherence-free scalable quantum processor. For the ease of the phase gate realization we employ one Raman laser field on four ions simultaneously, i.e. no tight focus for addressing. The decoherence-free subspace is left neither during gate operations nor during the transport of quantum information.

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Peter A. Ivanov, Ulrich G. Poschinger, Kilian Singer, Ferdinand Schmidt-Kaler. 2010-11-24. Quantum gate in the decoherence-free subspace of trapped ion qubits. https://doi.org/10.1209/0295-5075%2F92%2F30006

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