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arXiv · 2506.07220

Some features in 4-level generation in LIPLs

Lev Nagli·Kirill Kulikov·Dima Cheskis
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Abstract

This paper shows that in Laser-Induced Plasma Lasers (LIPL), the collisionally assisted transitions that lead to the inversion population on an upper-generation level E up may be partly forbidden. The spin-orbit coupling may increase the oscillator strength of such transitions. It also demonstrates that collisions between electrons and excited atoms can strongly increase the atoms' energy, creating a population inversion at the E up level, which may lie about 1 eV above the pumped level E pump . Examples of oscillator strengths and collisional transition rate estimates are provided using linear-response time-dependent density functional theory (TDDFT) in the Casida formalism.

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Lev Nagli, Kirill Kulikov, Dima Cheskis. 2025-06-08. Some features in 4-level generation in LIPLs. https://arxiv.org/abs/2506.07220

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