Observation of continuous coherent emission in methane at A = 3.39 μ m in spatially separated fields
Bagaev S.N. , Dychkov A.S. , Chebolaev V.P.
The interaction of two standing waves separated by a distance L with a rarefied gas is investigated. For the first time ever, observation of a new phenomenon is reported, namely continuously coherent emission produced at a distance 2L from the first field. The emission is due to transport of the polarization by the moving particles to large distances. The radiation intensity has a sharp maximum at the center of the line, with a width inversely proportional to the time of flight of the particles between the fields. The experiments were performed in methane at λ = 3.39 μπι (FP line).