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arXiv · 2510.26175

High-order Mie resonance and transient field enhancement in laser-driven plasma nanoshells

Xiaohui Gao
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Abstract

We demonstrate substantial field enhancement in plasma nanoshells through high-order Mie resonances using combined Mie theory and particle-in-cell simulations. Optimal shell geometries yield approximately threefold electric field enhancement for 800 nm irradiation, with transient buildup times of tens of femtoseconds before plasma expansion disrupts resonance. Few-cycle pulses produce reduced enhancement due to insufficient resonance establishment. These findings enable optimized laser-plasma interactions for applications including diagnostics of laser-cluster interaction and energetic ion production from engineered core-shell targets, highlighting the critical role of temporal dynamics in nanoplasma resonances.

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Xiaohui Gao. 2025-10-30. High-order Mie resonance and transient field enhancement in laser-driven plasma nanoshells. https://doi.org/10.1103/z4sw-kxlf

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