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Polarization phase gate with a tripod atomic system

S. Rebic·D. Vitali·C. Ottaviani·P. Tombesi·M. Artoni·F. Cataliotti·R. Corbalan
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Abstract

We analyze the nonlinear optical response of a four-level atomic system driven into a tripod configuration. The large cross-Kerr nonlinearities that occurr in such a system are shown to produce nonlinear phase shift of order $π$. Such a substantial shift may be observed in a cold atomic gas in a magneto-optical trap where it coupl be fasibly exploited towards the realization of a polarization quantum phase gate. The experimental feasibility of such a gate is here examined in detail.

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S. Rebic, D. Vitali, C. Ottaviani, P. Tombesi, M. Artoni, F. Cataliotti, R. Corbalan. 2004-03-15. Polarization phase gate with a tripod atomic system. https://doi.org/10.1103/physreva.70.032317

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