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Observation of Ultraslow Group Velocity of Light in a Solid

A. V. Turukhin·V. S. Sudarshanam·M. S. Shahriar·J. A. Musser·P. R. Hemmer
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Abstract

We report ultraslow group velocities of light in a solid. Light speeds as slow as 45 m/s were observed, corresponding to a group delay of 66 ms in a 3-mm thick crystal. Reduction of the group velocity is accomplished by using a sharp spectral feature in absorption and dispersion, produced by a Raman excited spin coherence in an optically dense Pr doped Y2SiO5 crystal.

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A. V. Turukhin, V. S. Sudarshanam, M. S. Shahriar, J. A. Musser, P. R. Hemmer. 2001-01-30. Observation of Ultraslow Group Velocity of Light in a Solid. https://arxiv.org/abs/quant-ph/0010009

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