Interaction of counterpropagating waves in the active medium of Raman lasers

An investigation was made of the competition between counterpropagating lasing waves in the active medium of an optically pumped far infrared Raman laser. A three-level model allowing for the longitudinal spatial harmonics of the polarization of the medium was used to calculate distributions of the far infrared field along the cell length. An analysis was made of the conditions for the occurrence and of the nature of the competition between the counterpropagating lasing waves. A comparison was made between the numerical modeling and experimental results.