Magnetic stabilization of the plasma column in flowing molecular lasers

A technique of magnetically stabilizing the position of the plasma column and the resulting inversion region in lower pressure flowing molecular lasers is described. A transverse magnetic field, mutually perpendicular to the discharge axial electric field and the gas flow velocity, is employed to maintain the electrical discharge column parallel with the optic axis. The magnetic stabilization of the discharge is analyzed in terms of the Lorentz forces and the resulting ambipolar drifts of the plasma. A comparison with magnetically stabilized arcs is presented. Supporting experimental data obtained for pure gases and typical laser gas mixtures are given. The operating characteristics of the cross-field CO2laser which employs a premixed gas flow channeled transverse to the stabilized discharge to provide convective gas cooling are discussed. The experimental results of a parametric study on the dependence of gain and power output upon gas flow velocities, magnetic field, gas mixtures, and pressure are presented. The operation of the first premixed CW electrically initiated chemical laser has been achieved using cross-field magnetic discharge stabilization. Preliminary operating characteristics of this chemical laser for the 3-µ rotational-vibrational transitions in HF and the 4-µ transitions in DF are presented.