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arXiv · 2606.29877

Broadband gain characterization of Co:MgF$_2$ for mid-infrared femtosecond pulse amplification

Natsuki Kanda·Kaito Nishimiya·Eiji J. Takahashi
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Abstract

The broadband gain characteristics of Co:MgF$_2$ were investigated to assess its potential as a gain medium for ultrashort-pulse amplification around the 2 $\mu$m spectral region. Single-pass gain measurements performed using femtosecond seed pulses revealed broadband amplification in the 1.5-2.4 $\mu$m region. The temporal dynamics and spectra of the gain were experimentally characterized and utilized for numerical simulations to assess the feasibility of Co:MgF$_2$ as a broadband gain medium for ultrashort pulses. The results indicate its potential for broadband amplification in future short-wave infrared to mid-infrared ultrafast laser systems, particularly when combined with coherent waveform synthesis or post-compression techniques.

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Natsuki Kanda, Kaito Nishimiya, Eiji J. Takahashi. 2026-06-29. Broadband gain characterization of Co:MgF$_2$ for mid-infrared femtosecond pulse amplification. https://arxiv.org/abs/2606.29877

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