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arXiv · 1212.3059

Realizing an $n$-target-qubit controlled phase gate in cavity QED: An approach without classical pulses

Qi-Ping Su·Man Liu·Chui-Ping Yang
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Abstract

We propose a way to realize a multiqubit controlled phase gate with one qubit simultaneously controlling $n$ target qubits using atoms in cavity QED. In this proposal, there is no need of using classical pulses during the entire gate operation. The gate operation time scales as $\sqrt{n}$ only and thus the gate can be performed faster when compared with sending atoms through the cavity one at a time. In addition, only three steps of operations are required for realizing this $n$-target-qubit controlled phase gate. This proposal is quite general, which can be applied to other physical systems such as various superconducting qubits coupled to a resonator, NV centers coupled to a microsphere cavity or quantum dots in cavity QED.

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Qi-Ping Su, Man Liu, Chui-Ping Yang. 2012-12-13. Realizing an $n$-target-qubit controlled phase gate in cavity QED: An approach without classical pulses. https://doi.org/10.1093/ptep%2Fpts092

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