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Sr
MnO
Tokuda, Makoto*; Mashimo, Tsutomu*; Khandaker, J. I.*; Ogata, Yudai; Mine, Yoji*; Hayami, Shinya*; Yoshiasa, Akira*
Journal of Materials Science, 51(17), p.7899 - 7906, 2016/09
Times Cited Count：2 Percentile：7.46(Materials Science, Multidisciplinary)Fujishima, Hironobu*; Okumura, Masahiko; Mine, Makoto*; Yajima, Tetsu*
Journal of the Physical Society of Japan, 81(10), p.104003_1 - 104003_7, 2012/10
Times Cited Count：1 Percentile：10.74(Physics, Multidisciplinary)We propose an indirect method for observing radiation from an incomplete soliton with a sufficiently large amplitude. We show that the radiation causes a notched structure on the envelope of the wave packet in the momentum space. The origin of this structure is the interference between the main body of oscillating solitons and the small radiation in the momentum space. We numerically integrate the nonlinear Schr
dinger equation and perform Fourier transformation to confirm that the predicted structure really appears. We also show a simple model which reproduces the qualitative result. The experimental detection of the notched structure with the Bose-Einstein condensation of neutral atoms is discussed and suitable parameters for this detection experiment are shown.
Fujishima, Hironobu*; Mine, Makoto*; Okumura, Masahiko; Yajima, Tetsu*
Journal of the Physical Society of Japan, 80(8), p.084003_1 - 084003_7, 2011/08
Times Cited Count：2 Percentile：20.07(Physics, Multidisciplinary)Potential scattering problems governed by the time-dependent Gross-Pitaevskii equation are investigated numerically for various values of coupling constants. The initial condition is assumed to have the Gaussian-type envelope, which differs from the soliton solution. The potential is chosen to be a box or well type. We estimate the dependences of reflectance and transmittance on the width of the potential and compare these results with those given by the stationary Schrdinger equation. We attribute the behaviors of these quantities to the limitation on the width of the nonlinear wave packet. The coupling constant and the width of the potential play an important role in the distribution of the waves appearing in the final state of scattering.
Kobayashi, Keita*; Mine, Makoto*; Okumura, Masahiko; Yamanaka, Yoshiya*
Soryushiron Kenkyu, 116(2), p.B64 - B66, 2008/06
no abstracts in English
Nakamura, Yusuke*; Mine, Makoto*; Okumura, Masahiko; Yamanaka, Yoshiya*
Soryushiron Kenkyu, 116(2), p.B67 - B69, 2008/06
no abstracts in English
Mine, Makoto*; Koide, Tomoi*; Okumura, Masahiko; Yamanaka, Yoshiya*
Soryushiron Kenkyu, 116(2), p.B110 - B112, 2008/06
no abstracts in English
Nakamura, Yusuke*; Mine, Makoto*; Okumura, Masahiko; Yamanaka, Yoshiya*
Physical Review A, 77(4), p.043601_1 - 043601_6, 2008/04
Times Cited Count：19 Percentile：65.63(Optics)The condition for the appearance of dynamical instability of the Bose- condensed system, characterized by the emergence of complex eigenvalues in the Bogoliubov-de Gennes equations, is studied analytically. It is concluded that the degeneracy between a positive- norm eigenmode and a negative-norm one is essential for the emergence of complex modes. Based on the conclusion, we justify the two-mode approximation applied in our previous work, in which we analytically studied the condition for the existence of complex modes when the condensate has a highly quantized vortex.
Fukuyama, Eriko*; Mine, Makoto*; Okumura, Masahiko; Sunaga, Tomoka*; Yamanaka, Yoshiya*
Physical Review A, 76(4), p.043608_1 - 043608_11, 2007/10
Times Cited Count：6 Percentile：33.45(Optics)We consider a trapped Bose-Einstein condensate (BEC) with a highly quantized vortex. For the BEC with a doubly, triply or quadruply quantized vortex, the numerical calculations have shown that the Bogoliubov-de Gennes equations, which describe the fluctuation of the condensate, have complex eigenvalues. In this paper, we obtain the analytic expression of the condition for the existence of complex modes, using the method developed by Rossignoli and Kowalski for the small coupling constant. To derive it, we make the two-mode approximation. With the derived analytic formula, we can identify the quantum numbers of the complex modes for each winding number of the vortex. Our result is consistent with those obtained by the numerical calculation in the case that the winding number is two, three or four. We prove that the complex modes always exist when the condensate has a highly quantized vortex.
Tsuji, Hiroshi; Okuno, Kiyoshi*; Thome, R.*; Salpietro, E.*; Egorov, S. A.*; Martovetsky, N.*; Ricci, M.*; Zanino, R.*; Zahn, G.*; Martinez, A.*; et al.
Nuclear Fusion, 41(5), p.645 - 651, 2001/05
Times Cited Count：57 Percentile：83.34(Physics, Fluids & Plasmas)no abstracts in English
/T target of muon-catalyzed fusion experimentsKudo, Hiroshi; Fujie, Makoto; Tanase, Masakazu; Kato, Mineo; Kurosawa, Kiyoyuki; Sugai, Hiroyuki; Umezawa, Hirokazu; Matsuzaki, Teiichiro*; Nagamine, Kanetada*
Applied Radiation and Isotopes, 43(5), p.577 - 583, 1992/00
no abstracts in English
-sticking phenomena in muon catalyzed fusion for a high density D-T mixture with 30% tritium concentrationNagamine, Kanetada*; Matsuzaki, Teiichiro*; Ishida, Katsuhiko*; *; *; *; Miyake, Yasuhiro*; *; *; *; et al.
Muon Catal. Fusion, 5-6, p.289 - 295, 1991/00
no abstracts in English
Kobayashi, Keita*; Mine, Makoto*; Okumura, Masahiko; Yamanaka, Yoshiya*
no journal, ,
no abstracts in English
Nakamura, Yusuke*; Mine, Makoto*; Okumura, Masahiko; Yamanaka, Yoshiya*
no journal, ,
no abstracts in English
Mine, Makoto*; Okumura, Masahiko; Sunaga, Tomoka*; Yamanaka, Yoshiya*
no journal, ,
no abstracts in English
Sunaga, Tomoka*; Fukuyama, Eriko*; Mine, Makoto*; Okumura, Masahiko; Yamanaka, Yoshiya*
no journal, ,
no abstracts in English
Dobashi, Kunio*; Shimizu, Yasuo*; Matsuzaki, Shinichi*; Ishizuka, Tamotsu*; Mori, Masatomo*; Sato, Takahiro; Koka, Masashi; Yokoyama, Akihito; Okubo, Takeru; Ishii, Yasuyuki; et al.
no journal, ,
no abstracts in English
Watanabe, Kazuhito; Nakamura, Makoto; Someya, Yoji; Masui, Akihiro; Katayama, Kazunari*; Hayashi, Takumi; Yanagihara, Satoshi*; Konishi, Satoshi*; Yokomine, Takehiko*; Torikai, Yuji*; et al.
no journal, ,
In the DEMO design, the blanket primary cooling system involves high temperature pressurized water (~300
C). This means the temperature of blanket structural material is higher than that of ITER. This increases tritium permeation ratio from the fusion plasma and blanket breeder to the primary cooling water. Therefore, we need to consider installation of a water detritiation system. In this study, we estimate the demand of water detritiation system from the view point of the amount of tritium permeated to primary cooling water that assumed conservatively. We also organize the issues for management of tritiated water from the other point of view based on the characteristic of the fusion DEMO reactor. The result shows that the existing facilities can be adopted to the DEMO if we can control the tritium ratio of primary cooling water as same as that of CANDU reactor.
Hanawa, Satoshi; Kawamura, Hirotaka*; Akamine, Hiroshi*; Shoda, Yasuhiko*; Nagase, Makoto*; Umehara, Ryuji*
no journal, ,
no abstracts in English
