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arXiv · 2607.18583

Acoustic Phonon Dynamics in Co-Doped BaFe$_2$As$_2$ Thin Film

Alexander Bartenev·Roman Kolodka·Larry Theran·Ki-Tae Eom·Jong-Hoon Kang·Jason Kawasaki·Chang-Beom Eom·Sergiy Lysenko
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Abstract

Pump-probe reflectivity reveals coherent acoustic oscillations at 33 and 8.2 GHz in a Ba(Fe$_{0.92}$Co$_{0.08}$)$_2$As$_2$ thin film. The acoustic response was analyzed using a modified logistic-function model, suggesting a temporal redistribution of coherent acoustic energy consistent with anharmonic decay of the higher-frequency mode into the lower-frequency mode.

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Alexander Bartenev, Roman Kolodka, Larry Theran, Ki-Tae Eom, Jong-Hoon Kang, Jason Kawasaki, Chang-Beom Eom, Sergiy Lysenko. 2026-07-20. Acoustic Phonon Dynamics in Co-Doped BaFe$_2$As$_2$ Thin Film. https://arxiv.org/abs/2607.18583

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