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arXiv · 2512.00795

Gigagauss magnetic field generation by bladed microtube implosion

D. Pan·M. Murakami
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Abstract

We demonstrate the generation of ultrahigh magnetic fields in the order of gigagauss using a bladed microtube target whose inner surface is periodically slanted in a sawtooth-like pattern. When irradiated by ultra-intense, ultrashort laser pulses, hot electrons with MeV energies are produced at the outer surface and swiftly transported to the inner surface, initiating a rapid implosion of plasma toward the central axis. The unique blade-induced asymmetry gives rise to vortex-shaped flows of ions and electrons near the center, forming strong azimuthal loop currents that generate ultrahigh magnetic fields at the center. Two-dimensional particle-in-cell simulations, supported by a simple analytical model, elucidate the underlying physics and reveal key scaling laws governing the field strength and spatial confinement.

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D. Pan, M. Murakami. 2025-11-30. Gigagauss magnetic field generation by bladed microtube implosion. https://doi.org/10.1063/5.0275006

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