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Lan, Z.*; Arikawa, Yasunobu*; Mirfayzi, S. R.*; Morace, A.*; Hayakawa, Takehito*; Sato, Hirotaka*; Kamiyama, Takashi*; Wei, T.*; Tatsumi, Yuta*; Koizumi, Mitsuo; et al.
Nature Communications (Internet), 15, p.5365_1 - 5365_7, 2024/07
Rapp, L.*; Matsuoka, Takeshi*; Firestein, K. L.*; Sagae, Daisuke*; Habara, Hideaki*; Mukai, Keiichiro*; Tanaka, Kazuo*; Gamaly, E. G.*; Kodama, Ryosuke*; Seto, Yusuke*; et al.
Physical Review Research (Internet), 6(2), p.023101_1 - 023101_18, 2024/04
It is generally known that irradiating a solid surface with a laser pulse of ultra-relativistic intensity generates a plasma on the surface, which in turn creates an ultrahigh pressure inside. In this study, the crystal structure analysis of high-pressure phases generated inside silicon single-crystals irradiated by this laser was performed using the diffraction system at the Stress and Imaging apparatus of BL22XU, which is a JAEA-BL. The results obtained confirm the existence of high-pressure phases that silicon is said to possess: body-centered, rhombohedral, hexagonal, and tetragonal phases in the interior. We can get the results that the crystal structure of silicon polymorphs of being include body-centered, rhombohedral, hexagonal-diamond, tetragonal exists. In the future, we will accumulate data and apply them to control the internal structure, strength, and functionality of materials.
Yogo, Akifumi*; Lan, Z.*; Arikawa, Yasunobu*; Abe, Yuki*; Mirfayzi, S. R.*; Wei, T.*; Mori, Takato*; Golovin, D.*; Hayakawa, Takehito*; Iwata, Natsumi*; et al.
Physical Review X, 13(1), p.011011_1 - 011011_12, 2023/01
Times Cited Count:17 Percentile:95.59(Physics, Multidisciplinary)Oks, E.*; Dalimier, E.*; Faenov, A.*; Pikuz, T.*; Fukuda, Yuji; Andreev, A.*; Koga, J. K.; Sakaki, Hironao; Kotaki, Hideyuki; Pirozhkov, A. S.; et al.
Optics Express (Internet), 23(25), p.31991 - 32005, 2015/12
Times Cited Count:7 Percentile:37.30(Optics)We present experiments dealing with a femtosecond laser-driven cluster-based plasma, where by analyzing the nonlinear phenomenon of satellites of spectral lines of Ar XVII, we revealed the nonlinear phenomenon of the generation of the second harmonic of the laser frequency. For performing this analysis we developed new results in the theory of satellites of spectral lines. From such lineshape analysis we found, in particular, that the efficiency of converting the short (40 fs) intense (310 W/cm) incident laser light into the second harmonic was 2%. This result is in the excellent agreement with the 2-Dimensional Particle-In-Cell (2D PIC) simulation that we also performed. There is also an order of magnitude agreement between the thresholds for the SHG found from the line shape analysis and from the 2D PIC simulations.
Pikuz, T.*; Faenov, A.*; Matsuoka, Takeshi*; Matsuyama, Satoshi*; Yamauchi, Kazuto*; Ozaki, Narimasa*; Albertazzi, B.*; Inubushi, Yuichi*; Yabashi, Makina*; Tono, Kensuke*; et al.
Scientific Reports (Internet), 5, p.17713_1 - 17713_10, 2015/12
Times Cited Count:39 Percentile:87.14(Multidisciplinary Sciences)Faenov, A.*; Matsubayashi, Masahito; Pikuz, T.*; Fukuda, Yuji; Kando, Masaki; Yasuda, Ryo; Iikura, Hiroshi; Nojima, Takehiro; Sakai, Takuro; Shiozawa, Masahiro*; et al.
High Power Laser Science and Engineering, 3, p.e27_1 - e27_9, 2015/10
Times Cited Count:10 Percentile:47.92(Optics)Zhidkov, A.*; Masuda, Shinichi*; Bulanov, S. S.*; Koga, J. K.; Hosokai, Tomonao*; Kodama, Ryosuke*
Physical Review Special Topics; Accelerators and Beams, 17(5), p.054001_1 - 054001_7, 2014/05
Times Cited Count:12 Percentile:61.44(Physics, Nuclear)Bulanov, S. V.; Esirkepov, T. Z.; Kando, Masaki; Koga, J. K.; Hosokai, Tomonao*; Zhidkov, A.*; Kodama, Ryosuke*
Physics of Plasmas, 20(8), p.083113_1 - 083113_10, 2013/08
Times Cited Count:22 Percentile:67.67(Physics, Fluids & Plasmas)Mizuta, Yoshio*; Hosokai, Tomonao*; Masuda, Shinichi*; Zhidkov, A.*; Makito, Keigo*; Nakanii, Nobuhiko*; Kajino, Shohei*; Nishida, Akinori*; Kando, Masaki; Mori, Michiaki; et al.
Physical Review Special Topics; Accelerators and Beams, 15(12), p.121301_1 - 121301_10, 2012/12
Times Cited Count:21 Percentile:71.29(Physics, Nuclear)Fukuda, Yuji; Faenov, A.*; Tampo, Motonobu; Pikuz, T.*; Nakamura, Tatsufumi; Kando, Masaki; Hayashi, Yukio; Yogo, Akifumi; Sakaki, Hironao; Kameshima, Takashi*; et al.
Progress in Ultrafast Intense Laser Science VII, p.225 - 240, 2011/05
We present substantial enhancement of the accelerated ion energies up to 10-20 MeV per nucleon by utilizing the unique properties of the cluster-gas target irradiated with 40-fs laser pulses of only 150 mJ energy, corresponding to approximately tenfold increase in the ion energies compared to previous experiments using thin foil targets. A particle-in-cell simulation infers that the high energy ions are generated at the rear side of the target due to the formation of a strong dipole vortex structure in sub-critical density plasmas. The demonstrated method can be important in the development of efficient laser ion accelerators for hadron therapy and other applications.
Kuramitsu, Yasuhiro*; Nakanii, Nobuhiko*; Kondo, Kiminori; Sakawa, Yoichi*; Mori, Yoshitaka*; Miura, Eisuke*; Tsuji, Kazuki*; Kimura, Kazuya*; Fukumochi, Shuji*; Kashihara, Mamoru*; et al.
Physical Review E, 83(2), p.026401_1 - 026401_6, 2011/02
Times Cited Count:17 Percentile:66.17(Physics, Fluids & Plasmas)An energy distribution function of energetic particles in the universe or cosmic rays is well represented by a power-law spectrum, therefore, nonthermal acceleration is essential to understand the origin of cosmic rays. A possible candidate for the origin of cosmic rays is wakefield acceleration at relativistic astrophysical perpendicular shocks. Substituting an intensive laser pulse for the large amplitude light waves, we performed a model experiment of the shock environments in a laboratory plasma.
Kuramitsu, Yasuhiro*; Nakanii, Nobuhiko*; Kondo, Kiminori; Sakawa, Yoichi*; Mori, Yoshitaka*; Miura, Eisuke*; Tsuji, Kazuki*; Kimura, Kazuya*; Fukumochi, Shuji*; Kashihara, Mamoru*; et al.
Physics of Plasmas, 18(1), p.010701_1 - 010701_4, 2011/01
Times Cited Count:20 Percentile:62.85(Physics, Fluids & Plasmas)Substituting an intensive laser pulse for the large amplitude light waves, we performed a model experiment of the shock environments in a laboratory plasma. An intensive laser pulse was propagated in a plasma tube created by imploding a hollow polystyrene cylinder, as the large amplitude light waves propagated in the upstream plasma at an astrophysical shock. Nonthermal electrons were generated, and the energy distribution functions of the electrons have a power-law component with an index of 2.
Nakamura, Tatsufumi; Tampo, Motonobu; Kodama, Ryosuke*; Bulanov, S. V.; Kando, Masaki
Physics of Plasmas, 17(11), p.113107_1 - 113107_6, 2010/11
Times Cited Count:40 Percentile:80.46(Physics, Fluids & Plasmas)Interactions of high contrast laser pulses with foam-attached targets are investigated via Particle-in-Cell (PIC) simulations in order to enhance the energy coupling from laser to plasmas. A foam layer whose mass density is much lower than that of the solid state is used for controlling the plasma density distribution of the laser irradiation region with the aid of the high contrast laser pulses. The ionization process plays a role in the laser and foam interaction, which results in the formation of periodic structure of ion charge density. The bulk electrons inside the foam layer are heated by the laser pulse, which results in the generation of abundant MeV electrons and higher energy coupling from laser to plasma. These features are utilized for laser ion acceleration by using a foam-attached thin foil target. It is shown that the laser accelerated ion energy is enhanced by properly choosing the foam parameters.
Zhidkov, A.*; Koga, J. K.; Hosokai, Tomonao*; Fujii, Takashi*; Oishi, Yuji*; Nemoto, Koshichi*; Kodama, Ryosuke*
Physics of Plasmas, 17(8), p.083101_1 - 083101_6, 2010/08
Times Cited Count:11 Percentile:38.64(Physics, Fluids & Plasmas)Tampo, Motonobu; Awano, Shinya*; Bolton, P.; Kondo, Kiminori; Mima, Kunioki*; Mori, Yoshitaka*; Nakamura, Hirotaka*; Nakatsutsumi, Motoaki*; Stephens, R. B.*; Tanaka, Kazuo*; et al.
Physics of Plasmas, 17(7), p.073110_1 - 073110_5, 2010/07
Times Cited Count:12 Percentile:41.29(Physics, Fluids & Plasmas)Fukuda, Yuji; Faenov, A. Y.; Tampo, Motonobu; Pikuz, T. A.*; Nakamura, Tatsufumi; Kando, Masaki; Hayashi, Yukio; Yogo, Akifumi; Sakaki, Hironao; Kameshima, Takashi*; et al.
Physical Review Letters, 103(16), p.165002_1 - 165002_4, 2009/10
Times Cited Count:170 Percentile:96.66(Physics, Multidisciplinary)A new approach for accelerating ions, based on the use of a cluster-gas target and a compact ultrashort pulse laser, is presented. It is shown that ions with energy 10-20 MeV per nucleon having a small divergence (full angle) of 3.4 are generated, corresponding to an approximately tenfold increase in the ion energies compared to previous experiments using solid targets. It is inferred from a particle-in-cell code simulation that the high energy ions are generated at the rear side of the target due to the formation of a strong dipole vortex structure in near-critical density plasmas.
Fukuda, Yuji; Faenov, A. Y.; Tampo, Motonobu; Pikuz, T. A.*; Nakamura, Tatsufumi; Kando, Masaki; Hayashi, Yukio; Yogo, Akifumi; Sakaki, Hironao; Kameshima, Takashi; et al.
AIP Conference Proceedings 1153, p.85 - 93, 2009/07
When the target consists of solid-density clusters embedded in the background gas, its irradiation by high intensity laser light renders ion acceleration a truly unique property. We present that the cluster-gas target, which consists of submicron-sized clusters and background gases, irradiated by a few TW laser pulse produces high energy ions upward of the order of 10-20 MeV/n in the forward direction.
Lei, A. L.*; Cao, L. H.*; Yang, X. Q.*; Tanaka, Kazuo*; Kodama, Ryosuke*; He, X. T.*; Mima, Kunioki*; Nakamura, Tatsufumi; Norimatsu, Takayoshi*; Yu, W.*; et al.
Physics of Plasmas, 16(2), p.020702_1 - 020702_4, 2009/02
Times Cited Count:12 Percentile:41.69(Physics, Fluids & Plasmas)The fast electron propagation in an inverse cone target is investigated computationally and experimentally. Two-dimensional particle-in-cell simulation shows that fast electrons with substantial numbers are generated at the outer tip of an inverse cone target irradiated by a short intense laser pulse. These electrons are guided and confined to propagate along the inverse cone wall, forming a large surface current. The experiment qualitatively verifies the guiding and confinement of the strong electron current in the wall surface. The large surface current and induced strong field s are of importance for fast ignition related research.
Nakamura, Hirotaka*; Chrisman, B.*; Tanimoto, Tsuyoshi*; Borghesi, M.*; Kondo, Kiminori; Nakatsutsumi, Motoaki*; Norimatsu, Takayoshi*; Tampo, Motonobu; Tanaka, Kazuo*; Yabuuchi, Toshinori*; et al.
Physical Review Letters, 102(4), p.045009_1 - 045009_4, 2009/01
Times Cited Count:25 Percentile:74.41(Physics, Multidisciplinary)Interactions between a relativistic-intensity laser pulse and a cone-wire target are studied by changing the focusing point of the pulse. The pulse, when focused on the sidewall of the cone, produced superthermal electrons with an energy 10 MeV, whereas less energetic electrons 1 MeV were produced by the pulse when focused on the cone tip. Efficient heating of the wire was indicated by significant neutron signals observed when the pulse was focused on the tip. Particle-in-cell simulation results show reduced heating of the wire due to energetic electrons produced by specularly reflected light at the sidewall.
Nakanii, Nobuhiko*; Kondo, Kiminori; Kuramitsu, Yasuhiro*; Mori, Yoshitaka*; Miura, Eisuke*; Tsuji, Kazuki*; Kimura, Kazuya*; Fukumochi, Shuji*; Kashihara, Mamoru*; Tanimoto, Tsuyoshi*; et al.
Applied Physics Letters, 93(8), p.081501_1 - 081501_3, 2008/08
Times Cited Count:4 Percentile:18.46(Physics, Applied)Energetic electrons were generated by the interaction of a high-intensity laser pulse with a plasma preformed from a hollow plastic cylinder via laser-driven implosion. The spectra of a comparatively high-density plasma had a bump around 10 MeV. Simple numerical calculations explained the spectra obtained in this experiment. This indicates that the plasma tube has sufficient potential to convert a Maxwellian spectrum to a comparatively narrow spectrum.