TE-CO2 injection laser: status and perspectives

摘要

Within the framework of our LIDAR activity devoted to air pollution measurements, we realized the injection of a continuous carbon dioxide laser into a high power TE CO$-2$/ laser, to get the possibility of better analyze return signal response and to realize a Doppler wind velocimeter. Apart from the need of temporally smooth pulse to examine measurements result, in remote sensing it is desirable to use narrow band laser sources. The request of high spectral performances is manly based on the possibility to use heterodyne detection, on one hand, to improve the signal to noise ratio, and, on the other, to observe and analyze Doppler frequency shift in the return signal. We are engaged into implement a TE CO$-2$/ laser source by injection of a cw pulse from a low pressure CO$-2$/. Preliminary results we obtained show a smoothing of the output pulse shape and a consequent reduction in spectral band-width, revealing a single longitudinal mode operation.