Adiabatic inversion of population and nonlinear absorption of light by accelerated atoms

Janusz Czub, W. Miklaszewski

The adiabatically created population inversions in S 1/2 -P 1/2 , S 1/2 -P 3/2 and S 1/2 -P 1/2,3/2 systems colliding with buffer gas atoms and interacting with a light pulse with varying driving frequency are investigated. The validity of the adiabatic and secular-adiabatic approximations is examined. A collisionally induced population inversion is predicted. The numerical simulation is performed.

Овчинников

Yang Li-Jun, Teng Ma, Sun Ke-Jia +1 more

In this paper, we investigate the spectrum properties of the lasing without population inversion in a three-level atomic system under an action of an externally applied microwave field. The probed absorption spectrum is obtained by solving the density matrix equation of this system. The results show that the absorption profile has a multi-peak structure, and exhibits obviously negative absorption (light amplification) in a specific range under the action of strong microwave field. The characteristic of the light amplification without population inversion according to the three level atomic system is demonstrated by the quantitative analysis of populations related to the probe levels.

E. B. Treacy

Sergey G. Rautian, Gennady I. Smirnov

Yifu Zhu, Joseph Saldana, Lingling Wen +1 more

We show that electromagnetically induced transparency suppresses nonlinear absorption of all orders in a multilevel atomic system and leads to selective, multiphoton excitation of resonantly coupled atomic states. Under appropriate conditions, higher-order nonlinear absorption becomes dominant and selective steady-state population inversion is created among the resonantly coupled states.