Gain and threshold in noninversion lasers

C. Saavedra, J. C. Retamal, Christoph H. Keitel

Marlan O. Scully, Shi-Yao Zhu, Lorenzo M. Narducci +1 more

The influence of the atomic lifetime and Raman field strength on the gain and laser threshold in noninverted atomic systems is studied. Results show that to achieve useful gain in such a system, it is necessary to use a sufficiently intense Raman field, atoms with a long lifetime for the lower active levels, and a small cavity loss.

Kai J. Drühl, Marlan O. Scully, A. W. Overhauser

Zhenfei Luo, Zhizhan Xu

A noninversion laser system which is closed lifetime broadened and free of the restriction on atomic decay rates is proposed. For the realization of lasing without inversion, the Rabi frequency of the applied field must exceed a lower threshold. Moreover, the coherence term in dressed states must enhance the gain. These results are obtained beyond the specific approximations.

L. A. Pokrovskii

Rafael V Ambartsumyan, Nikolai G. Basov, Peter G. Kryukov +1 more