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arXiv · 0711.0064

Subnatural linewidth using electromagnetically induced transparency in Doppler-broadened vapor

S. M. Iftiquar·G. R. Karve·Vasant Natarajan
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Abstract

We obtain subnatural linewidth (i.e. $<\Gamma$) for probe absorption in room-temperature Rb vapor using electromagnetically induced transparency (EIT) in a $\Lambda$ system. For stationary atoms, the EIT dip for a resonant control laser is as wide as the control Rabi frequency $\Omega_c$. But in thermal vapor, the moving atoms fill the transparency band so that the final EIT dip remains subnatural even when $\Omega_c > \Gamma$. We observe linewidths as small as $\Gamma/7$ in the $D_2$ line of Rb.

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S. M. Iftiquar, G. R. Karve, Vasant Natarajan. 2007-11-01. Subnatural linewidth using electromagnetically induced transparency in Doppler-broadened vapor. https://doi.org/10.1103/physreva.77.063807

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