Population inversion in a three-level system

S. Basile, P. Lambropoulos

Yu. P. Malakyan, Razmik G. Unanyan

Wytze E. van der Veer, R. J. J. van Diest, H. B. van Linden van den Heuvell

Guiyin Zhang, Shicheng Hu, Jianjie Li +3 more

Galina Nemova

Yifu Zhu

It is shown that a closed V-type, three-level system, which is incoherently pumped on the transition at which lasing occurs and coherently pumped on the other transition, exhibits lasing without population inversion in any atomic state basis. The same system can be also made to exhibit lasing without population inversion in the bare atomic state basis but with population inversion in the dressed-state basis.