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Transient dynamics of light propagation in EIT medium and hidden symmetry of multi-bit quantum memory

Y. Li·X. F. Liu·C. P. Sun
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Abstract

We investigate the transient phenomenon or property of the propagation of an optical probe field in a medium consisting of many $Λ$-type three-level atoms coupled to this probe field and an classical driven field. We observe a hidden symmetry and obtain an exact solution for this light propagation problem by means of the spectral generating method. This solution enlightens us to propose a practical protocol implementing the quantum memory robust for quantum decoherence in a crystal. As an transient dynamic process this solution also manifests an exotic result that a wave-packet of light will split into three packets propagating at different group velocities. It is argued that "super-luminal group velocity" and "sub-luminal group velocity" can be observed simultaneously in the same system. This interesting phenomenon is expected to be demonstrated experimentally.

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Y. Li, X. F. Liu, C. P. Sun. 2003-06-25. Transient dynamics of light propagation in EIT medium and hidden symmetry of multi-bit quantum memory. https://arxiv.org/abs/quant-ph/0306170

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