Mode-Locking of an Atmospheric Pressure Cross-Excited Electrically Pulsed CO2 Laser

摘要

Self-mode-locking of a cross-excited electrically pulsed CO2 laser has been observed and studied as a function of cavity length and operating pressure. The best results are achieved with a 2.2 meter cavity having an active length of 1.5 meters. At a pressure of 450 Torr three axial modes are locked to give a train of 5 nsec pulses. Shorter pulses on the order of 2-3 nsec are seen at higher pressures, but the modulation and pulse shape are not as reproducible. With longer cavities more axial modes are locked, resulting in a longer dead time between pulses; however, the pulse widths increase. This indicates that less of the bandwidth is utilized with closely spaced axial modes. (Author)