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arXiv · 1409.0460

Effects of temperature and ground-state coherence decay on enhancement and amplification in a $Δ$ atomic system

Manukumara Manjappa·Satya Sainadh Undurti·Asha Karigowda·Andal Narayanan·Barry C. Sanders
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Abstract

We study phase-sensitive amplification of electromagnetically induced transparency in a warm ${}^{85}$Rb vapor wherein a microwave driving field couples the two lower-energy states of a Λ energy-level system thereby transforming into a Δ system. Our theoretical description includes effects of ground-state coherence decay and temperature effects. In particular, we demonstrate that driving-field-enhanced electromagnetically induced transparency is robust against significant loss of coherence between ground states. We also show that for specific field intensities, a threshold rate of ground-state coherence decay exists at every temperature. This threshold separates the probe-transmittance behavior into two regimes: probe amplification vs probe attenuation. Thus, electromagnetically induced transparency plus amplification is possible at any temperature in a Δ system.

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Manukumara Manjappa, Satya Sainadh Undurti, Asha Karigowda, Andal Narayanan, Barry C. Sanders. 2014-10-31. Effects of temperature and ground-state coherence decay on enhancement and amplification in a $Δ$ atomic system. https://doi.org/10.1103/physreva.90.043859

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