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Coupled cavities for enhancing the cross-phase modulation in electromagnetically induced transparency

T. Opatrny·D. -G. Welsch
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Abstract

We propose an optical double-cavity resonator whose response to a signal is similar to that of an Electromagnetically Induced Transparency (EIT) medium. A combination of such a device with a four-level EIT medium can serve for achieving large cross-Kerr modulation of a probe field by a signal field. This would offer the possibility of building a quantum logic gate based on photonic qubits. We discuss the technical requirements that are necessary for realizing a probe-photon phase shift of Pi caused by a single-photon signal. The main difficulty is the requirement of an ultra-low reflectivity beamsplitter and to operate a sufficiently dense cool EIT medium in a cavity.

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T. Opatrny, D. -G. Welsch. 2001-05-02. Coupled cavities for enhancing the cross-phase modulation in electromagnetically induced transparency. https://doi.org/10.1103/physreva.64.023805

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