Qianfeng Yin

1 Introduction The study of the magnetosphere-ionosphere (M-I) coupling has been a major focus of research in the field of geospace for several decades (Goertz & Boswell, 1979) due to its importance in space weather forecasting. As magnetospheric currents flow into and out of the conductive polar ionosphere along equipotential magnetic field lines, a coupled M-I current system is formed.

3D Printable, Tough, Magnetic Hydrogels with Programmed Magnetization for Fast Actuation Magnetic hydrogels have demonstrated great potential in soft robots, drug delivery, and bioengineering, and their functions are usually determined by the deforming capabilities. However, most magnetic hydrogels are embedded with soft magnetic particles (e.g. Fe3O4), where the magnetic domains cannot be programmed and retained under external magnetic fields.