As. Zibrov et al., EXPERIMENTAL DEMONSTRATION OF ENHANCED INDEX OF REFRACTION VIA QUANTUM COHERENCE IN RB, Physical review letters, 76(21), 1996, pp. 3935-3938
We present a proof-of-principle experiment demonstrating a resonant en
hancement of the index of refraction accompanied by vanishing absorpti
on in a cell containing a coherently prepared Rb vapor. The results ar
e in good agreement with detailed theoretical predictions.