High-Power Electron-Beam Controlled CO2 Lasers

This chapter discusses the technology associated with one of the laser devices: the electron-beam-controlled carbon dioxide laser operating at a wavelength of 9 to 10 µm. It outlines the process and state the results in a form usable for predicting the gain coefficient of an EBCL laser over a useful range of operating parameters. Laser devices have been developed that use gas, solid, and liquid media, that operate from the ultraviolet region to the far infrared, and that deliver average optical powers of milliwatts to hundreds of kilowatts and peak powers as high as tens of terawatts. The process most frequently used to place large numbers of CO₂ molecules in their “upper” state is inelastic scattering on CO₂ and N₂ by “low”-energy electrons. Indeed, sometimes the challenge will be to generate an electron beam current with a suitably low value, in order to match the discharge impedance to the power supply impedance and maintain the highest laser efficiency.