Speaker
Norimasa Ozaki
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P1.2006.pdf
XFEL observation of shock-compressed highly oriented graphite
Norimasa Ozaki1,2 , Kento Katagiri1 , Ryo Hazama1 , Takahiro Matsuoka3 , Takeshi Matsuoka4 ,
Kohei Miyanishi2 , Yuhei Umeda1 , Yusuke Seto5 , Yuichi Inubushi6 , Toshinori Yabuuchi6 ,
Tadashi Togashi6 , Makina Yabashi7 , and Ryosuke Kodama1,2
1 Graduate School of Engineering, Osaka University, Suita, Japan
2 Institute of Laser Engineering, Osaka University, Suita, Japan
3 Graduate School of Engineering, Gifu University, Gifu, Japan
4 Open and Transdisciplinary Research Initiative, Osaka Univeristy, Suita, Japan
5 Graduate School of Science, Kobe University, Kobe, Japan
6 JASRI/SPring-8, Sayo, Japan
7 RIKEN SPring-8 Center, Sayo, Japan
High power laser-driven shock is widely used to investigate the states and behaviors of ma-
terial in extreme conditions associated with warm dense matter (WDM) physics, planetary sci-
ences, and inertial fusion energy research[1]. At the high pressure and extremely high strain
rate conditions, it is known that mechanical properties and behaviors of material can change
significantly more than expected. Such properties change is influenced by the micro-structure
of material. We here present experimental results on X-ray free electron laser (XFEL) observa-
tions of shock-compressed highly oriented materials at the SACLA-HEDS platform [2, 3, 4].
We shock compressed highly oriented pyrolytic graphite (HOPG) samples along the [002] ori-
entation using a 3-4 ns optical laser pulse and observed the lattices under the shock compression
using the XFEL pulse with changing the time delay between the optical and X-ray pulses. Once
the HOPG interlayers were compressed uniaxially up to ∼20% or more, and then a high pressure
form of carbon was created on picosecond time scale above ∼20 GPa pressures. This sequence
might be different from reported very recently [5, 6].
This work was supported by a Grant-in-Aid for Scientific Research, KAKENHI (Grant No.
15K13609 and 16H02246), the Genesis Research Institute, Inc. (Konpon-ken, TOYOTA), and
XFEL Priority Strategy Program at Osaka Univ. from the MEXT.
References
[1] N. Ozaki, W. J. Nellis, T. Mashimo et al., Sci. Rep. 6, 26000 (2016).
[2] T. Pikuz, A. Faenov, T. Matsuoka et al., Sci. Rep. 5, 17713 (2015).
[3] N. J. Hartley, N. Ozaki, T. Matsuoka et al., Appl. Phys. Lett. 110, 071905 (2017).
[4] B. Albertazzi, N. Ozaki, V. Zhakhovsky et al., Sci. Adv. 3, e1602705 (2017).
[5] D. Kraus, A. Ravasio, M. Gauthier et al., Nat. Comm. 3, e1602705 (2017).
[6] S. J. Turneaure, S. M. Sharma, T. J. Volz et al., Sci. Adv. 3, eaao3561 (2017).
