Compact pulsed intense magnetic field generator for Shenguang-II upgrade laser facility

Abstract

A compact pulsed intense magnetic field generator is presented for magnetized laser plasma experiments at the Shenguang-II upgrade laser facility (Shanghai). The pulsed magnetic field device can generate a 45 kA peak current with 480 ns rising time at a discharge voltage of 40 kV, time jitter is about 100 ns. The peak magnetic field reaches 9 T using a double-twisted coil of 12 mm diameter. A specially designed tunable transmission line was developed to realize the flexible connection between the capacitor bank and the magnetic field coil. The setup is compatible with the particular target chamber of the laser facility. Thus the coil component can be adjusted separately by the three-dimensional motorized translation stage placed in the target chamber, with 10 cm (transverse) and 1 cm (longitudinal) adjustable scales and 6 μm precision. A high-voltage electric-trigger spark-gap gas switch was used to reduce the operation complexity and the occupied area of the generator. Grounding and shielding structure ensure fine electromagnetic compatibility with the target chamber. The device has been successfully operated in magnetized laser plasma experiments performed on the laser facility.