Increase in gain on TEA-CO2 laser device with supersonic flow

The small-signal gain of a TEA-CO₂ laser medium is evaluated under the supersonic flow condition at M= 2. The gain is measured at 2.2 %/cm for the supersonic flow of the gas at 133 K in temperature, which is 1.3 times as high as that obtained for the still laser gas medium at the room temperature. The results suggest the possibility that the output power of the TEA-CO₂ laser can be increased by utilizing the supersonic flow.