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Three-Way Entanglement and Three-Qubit Phase Gate Based on a Coherent Six-Level Atomic System

Chao Hang·Yun Li·Lei Ma·Guoxiang Huang
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Abstract

We analyze the nonlinear optical response of a six-level atomic system under a configuration of electromagnetically induced transparency. The giant fifth-order nonlinearity generated in such a system with a relatively large cross-phase modulation effect can produce efficient three-way entanglement and may be used for realizing a three-qubit quantum phase gate. We demonstrate that such phase gate can be transferred to a Toffoli gate, facilitating practical applications in quantum information and computation.

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Chao Hang, Yun Li, Lei Ma, Guoxiang Huang. 2006-02-26. Three-Way Entanglement and Three-Qubit Phase Gate Based on a Coherent Six-Level Atomic System. https://doi.org/10.1103/physreva.74.012319

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