Transonic Dislocation Propagation in Diamond

Kento Katagiri; Tatiana Pikuz; Lichao Fang; Bruno Albertazzi; Shunsuke Egashira; Yuichi Inubushi; Genki Kamimura; Ryosuke Kodama; Michel Koenig; Bernard Kozioziemski; Gooru Masaoka; Kohei Miyanishi; Hirotaka Nakamura; Masato Ota; Gabriel Rigon; Youichi Sakawa; Takayoshi Sano; Frank Schoofs; Zoe J. Smith; Keiichi Sueda; Tadashi Togashi; Tommaso Vinci; Yifan Wang; Makina Yabashi; Toshinori Yabuuchi; Leora E. Dresselhaus-Marais; Norimasa Ozaki

arXiv · 2303.04370

Transonic Dislocation Propagation in Diamond

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Abstract

The motion of line defects (dislocations) has been studied for over 60 years but the maximum speed at which they can move is unresolved. Recent models and atomistic simulations predict the existence of a limiting velocity of dislocation motions between the transonic and subsonic ranges at which the self-energy of dislocation diverges, though they do not deny the possibility of the transonic dislocations. We use femtosecond x-ray radiography to track ultrafast dislocation motion in shock-compressed single-crystal diamond. By visualizing stacking faults extending faster than the slowest sound wave speed of diamond, we show the evidence of partial dislocations at their leading edge moving transonically. Understanding the upper limit of dislocation mobility in crystals is essential to accurately model, predict, and control the mechanical properties of materials under extreme conditions.

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Kento Katagiri, Tatiana Pikuz, Lichao Fang, Bruno Albertazzi, Shunsuke Egashira, Yuichi Inubushi, Genki Kamimura, Ryosuke Kodama, Michel Koenig, Bernard Kozioziemski, Gooru Masaoka, Kohei Miyanishi, Hirotaka Nakamura, Masato Ota, Gabriel Rigon, Youichi Sakawa, Takayoshi Sano, Frank Schoofs, Zoe J. Smith, Keiichi Sueda, Tadashi Togashi, Tommaso Vinci, Yifan Wang, Makina Yabashi, Toshinori Yabuuchi, Leora E. Dresselhaus-Marais, Norimasa Ozaki. 2023-03-08. Transonic Dislocation Propagation in Diamond. https://arxiv.org/abs/2303.04370

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