Exotic transport of high-current relativistic electron beams in porous materials

by Prof. Ke Jiang(蒋轲) (Shenzhen Tech. University)

Monday 23 Nov 2026, 14:00 → 15:00 Asia/Shanghai

Tsung-Dao Lee Institute/S4F-SW - Open Area (Tsung-Dao Lee Institute)

Host: Longqing Yi
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Abstract：
Transport of high-current relativistic electron beams (REBs) through matter is fundamental to high-energy-density physics, with applications in fast ignition, radiation generation, and laboratory astrophysics. Conventional collisional stopping theories, such as the Bohr-Fermi-Bethe-Bloch (BFBB) framework, describe energy loss when collective beam effects are negligible. At megaampere currents, however, beam-driven return currents and collective electromagnetic effects become essential. Existing collisional theories and homogeneous-plasma models cannot fully capture REB transport in complex media, where microscopic heterogeneity strongly influences collective beam dynamics. Here, we report three distinct transport phenomena arising from the interplay between high-current REBs and porous microstructures: branched flows, in which the beam splits into multiple tree-like branches; superchanneling, in which the beam self-organizes into a dense, stable, and strongly radiating filament; and anomalous stopping, in which low-density porous materials stop REBs more effectively than denser counterparts. These seemingly different phenomena share a common physical origin in stochastic yet spatially correlated multi-kilotesla magnetic fields generated by return currents flowing along the solid skeletons. Building on these findings, we outline a roadmap toward a unified phase diagram in the parameter space of beam density, beam energy, and pore size. These findings establish porous microstructure as a new degree of freedom for controlling intense electron-beam transport, with promising implications for fast ignition, advanced radiation sources, and laboratory astrophysics.

Biography:
Ke Jiang is an Associate Professor at the College of Engineering Physics, Shenzhen Technology University. He received his Ph.D. in Plasma Physics from the China Academy of Engineering Physics in 2021 and was a visiting doctoral researcher at Heinrich Heine University Düsseldorf, Germany. His research focuses on intense laser-matter interactions and high-current relativistic electron beam transport. He has pioneered studies of collective transport in disordered porous media, uncovering novel phenomena including branched flows, superchanneling, and anomalous stopping. His research has resulted in three first- or co-first-author papers in Physical Review Letters, including one selected as an Editors’ Suggestion and featured in a Focus story by APS Physics. He has led research projects funded by the National Natural Science Foundation of China and delivered invited talks at international conferences. He also serves on the editorial boards of Laser and Particle Beams and Chinese Laser Press.