A New Method for Magnetic Gain Modulation of Chemical Oxygen Iodine Laser Based on Flat-Top Pulsed Magnetic Field

Chemical oxygen iodine laser (COIL) is widely used in material processing and industrial medicine due to the extremely high coupling efficiency to metals. COIL's pulse mode can greatly increase peak power. Magnetic gain modulation is the important technique to achieve COIL pulse mode. This article proposes a new method of combining flat-top pulsed magnetic field with permanent magnets to achieve magnetic gain modulation of COIL. The permanent magnets provide a static magnetic field, which is superimposed on the flat-top pulsed magnetic field for fast magnetic field removal to achieve ideal magnetic gain modulation. A new circuit structure for fast generation of flat-top pulsed magnetic field has been developed. The experimental results show that the flat-top pulsed circuit discharges the coil to produce a flat-top magnetic field that approximates a square wave. The 405 G static magnetic field can be cleared instantly in 50 x 50 x 30 mm(3) resonant cavity. The drop time and clearing time of the magnetic field is 1.5 and 3 mu s, respectively.