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Quantum Phase Gate Operation Based on Nonlinear Optics: Full Quantum Analysis

C. Ottaviani·S. Rebic·D. Vitali·P. Tombesi
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Abstract

We present a full quantum treatment of a five-level atomic system coupled to two quantum and two classical light fields. The two quantum fields undergo a cross-phase modulation induced by electro-magnetically induced transparency. The performance of this configuration as a two-qubit quantum phase gate for travelling single-photons is examined. A trade-off between the size of the conditional phase shift and the fidelity of the gate is found. Nonetheless, a satisfactory gate performance is still found to be possible in the transient regime, corresponding to a fast gate operation.

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C. Ottaviani, S. Rebic, D. Vitali, P. Tombesi. 2006-01-09. Quantum Phase Gate Operation Based on Nonlinear Optics: Full Quantum Analysis. https://doi.org/10.1103/physreva.73.010301

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