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Strong electromagnetically induced transparency in atomic media with large residual Doppler broadening

Luis E. E. de Araujo·Silvania A. Carvalho·Luciano S. Soares·Antonio A. Soares·Armando Mirage·Daniel Pereira·Flavio C. Cruz
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Abstract

Electromagnetically induced transparency and coherent population trapping were observed in a hot (1000 K) calcium vapor embedded into an electrical gas discharge. Unexpectedly large transparencies (of up to 70%) were observed under very unfavorable conditions: probe wavelength shorter than the coupling wavelength, and coupling Rabi frequency significantly smaller than the residual Doppler linewidth of the two photon transition. We developed a theoretical model that shows that the observed results are due to the combined effects of a strong probe beam and a small open character of the atomic system. Coherent population trapping also manifests itself as a change in the impedance of the gas discharge, and the phenomenon can be probed with high sensitivity via the optogalvanic effect.

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Luis E. E. de Araujo, Silvania A. Carvalho, Luciano S. Soares, Antonio A. Soares, Armando Mirage, Daniel Pereira, Flavio C. Cruz. 2006-11-30. Strong electromagnetically induced transparency in atomic media with large residual Doppler broadening. https://arxiv.org/abs/quant-ph/0611291

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