Chinese Journal of Quantum Electronics

Saturation effect and velocity selective population of 5S_(1/2)→5P_(3/2) with laser excitation in Rb-H_2 vapor

Yifan Shen

Published Jan 1, 2008• 0 citations

Abstract

Excited state population distribution of 5S_(1/2)→5P_(3/2)with laser excitation in room temperature rubidium vapor mixed with H_2 was quantitatively analyzed by absorption and saturation spectroscopy. When the laser linewidth is much smaller than the Doppler linewidth,the absorption coefficients were measured for a series of laser powers between 40 #W and 5 mW at 780 nm.Population in the 5P_(3/2)level obtained from the saturation measurements was also determined by the absorption measurement of narrow spectral line from a Rb hollow cathode lamp.The results obtained in these two ways arin good agreement. When the H_2 pressure was 100 Pa,it was shown that 8% of the ground state population could be transferred to the first excited state by pumping the Doppler broadened line with a single-mode narrow-band laser.

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