Time-varying beam quality factor and mode evolution in TEA CO2 laser pulses

摘要

The time evolution of the transversal modes in a TEAnCO2 laser cavity has been investigated from the analysis ofnthe time-varying beam quality factor M2 of the emittednpulses. The experiments reveal a significant change in this parameternduring the pulse evolution, which can be translated into an evolution ofnthe modes of the laser cavity to reach a nearly stationary behavior.nAttention is focused on both the appearance of a particular mode and thenduration of its growing process