Spin mixing conductance at a well-controlled platinum/yttrium iron garnet interface

Qiu, Z.*; Ando, Kazuya*; Uchida, Kenichi*; Kajiwara, Yosuke*; Takahashi, Ryo*; Nakayama, Hiroyasu*; An, Toshu*; Fujikawa, Yasunori*; Saito, Eiji

Applied Physics Letters, 103(9), p.092404_1 - 092404_4, 2013/08

https://doi.org/10.1063/1.4819460

A platinum (Pt)/yttrium iron garnet (YIG) bilayer system with a well-controlled interface has been developed; spin mixing conductance at the Pt/YIG interface has been studied. A clear interface with good crystal perfection is experimentally demonstrated to be one of the important factors for an ultimate spin mixing conductance. The spin mixing conductance is obtained to be 1.310m at the well-controlled Pt/YIG interface, which is close to a theoretical prediction.

Interface induced inverse spin Hall effect in bismuth/permalloy bilayer

Hou, D.*; Qiu, Z.*; Harii, Kazuya; Kajiwara, Yosuke*; Uchida, Kenichi*; Fujikawa, Yasunori*; Nakayama, Hiroyasu*; Yoshino, Tatsuro*; An, Toshu*; Ando, Kazuya*; et al.

Applied Physics Letters, 101(4), p.042403_1 - 042403_4, 2012/07

https://doi.org/10.1063/1.4738786

Inverse spin Hall effect has been investigated in bismuth(Bi)/permalloy(Py) bilayer films by using the spin pumping at room temperature. From the ferromagnetic-resonance-spectrum linewidth data, Bi is proved to be a good spin sink in our structure. We measured inverse spin Hall voltage and conductance of the Bi/Py bilayer and found that the inverse spin Hall current, , decreases with increasing the Bi thickness, which is in contrast to the former understanding in similar bilayer systems, e.g., Pt/Py. We constructed a model to explain the thickness dependence of quantitatively, in which spin transport modulation near Bi/Py interface is considered.

Optical features of a LiF crystal soft X-ray imaging detector irradiated by free electron laser pulses

Pikuz, T.; Faenov, A.*; Fukuda, Yuji; Kando, Masaki; Bolton, P.; Mitorfanov, A.*; Vinogradov, A.*; Nagasono, Mitsuru*; Ohashi, Haruhiko*; Yabashi, Makina*; et al.

Optics Express (Internet), 20(4), p.3424 - 3433, 2012/02

https://doi.org/10.1364/OE.20.003424

Benchmark calculations of sodium-void experiments with uranium fuels at the fast critical assembly FCA

Fukushima, Masahiro; Kitamura, Yasunori; Kugo, Teruhiko; Yamane, Tsuyoshi; Ando, Masaki; Chiba, Go; Ishikawa, Makoto; Okajima, Shigeaki

Progress in Nuclear Science and Technology (Internet), 2, p.306 - 311, 2011/10

https://doi.org/10.15669/pnst.2.306

Two-temperature warm dense matter produced by ultrashort Extreme Vacuum Ultraviolet-Free Electron Laser (EUV-FEL) pulse

Inogamov, N. A.*; Faenov, A. Ya.*; Zhakhovsky, V. V.*; Pikuz, T. A.*; Skobelev, I. Yu.*; Petrov, Y. V.*; Khokhlov, V. A.*; Shepelev, V. V.*; Anisimov, S. I.*; Fortov, V. E.*; et al.

Contributions to Plasma Physics, 51(5), p.419 - 426, 2011/06

https://doi.org/10.1002/ctpp.201110013

Warm dense matter, arising under the action of ultrashort EUV-FEL pulse onto LiF dielectric crystal, is characterized by high temperature of conduction electrons, with their number density achieving values of the order of atom number density at maximum laser fluences in our experiments. Expansion of matter, heated and pressurized through the electron-ion energy exchange, gives rise to the spallative ablation at small fluences and gaseous outflow from a target in the case of large fluences. Ablation threshold is low in comparison with a longer nanosecond XRL.

Inverse spin-Hall effect induced by spin pumping in different size NiFe/Pt films

Nakayama, Hiroyasu*; Ando, Kazuya*; Harii, Kazuya*; Fujikawa, Yasunori*; Kajiwara, Yosuke*; Yoshino, Tatsuro*; Saito, Eiji

Journal of Physics; Conference Series, 266, p.012100_1 - 012100_4, 2011/01

https://doi.org/10.1088/1742-6596/266/1/012100

The inverse spin-Hall effect, conversion of spin currents into electric voltage, has been investigated in NiFe/Pt bilayer films with different length and width. We measured the electric voltage generated by the inverse spin-Hall effect induced by the spin pumping at room temperature. The experimental results indicate that the electric voltage induced by the inverse spin-Hall effect is proportional to the length of NiFe/Pt bilayer films. In contrast, the electric voltage exhibits almost no variation by changing the width of the NiFe/Pt films. These results are consistent with the inverse spin-Hall effect model.

Application of NBI technologies

Watanabe, Kazuhiro; Ando, Yasunori*

Purazuma, Kaku Yugo Gakkai-Shi, 81(10), p.792 - 797, 2005/10

https://doi.org/10.1585/jspf.81.792

no abstracts in English

Achievement of high fusion triple product in the JT-60U high H mode

Mori, Masahiro; Ishida, Shinichi; Ando, Toshiro; ; Asakura, Nobuyuki; Azumi, Masafumi; A.A.E.van-Blokland*; G.J.Frieling*; Fujii, Tsuneyuki; Fujita, Takaaki; et al.

Nuclear Fusion, 34(7), p.1045 - 1053, 1994/00

https://doi.org/10.1088/0029-5515/34/7/I09

no abstracts in English

Development of reactivity feedback effect measurement techniques under sub-critical condition in fast reactor, 1-1; Purpose and program

Okajima, Shigeaki; Nishi, Hiroshi; Yamane, Yoshihiro*; Kanemoto, Shigeru*; Yamane, Tsuyoshi; Mori, Takamasa; Kitamura, Yasunori; Fukushima, Masahiro; Kitano, Akihiro; Ando, Masaki; et al.

no journal, , 

The program was planned and has been carried out to develop of the reactivity feedback effect measurement techniques under sub-critical condition in the start-up experiment for fast reactors. The program includes the demonstration of the developed technique in fast critical assembly (FCA) and the proposal of the appropriate measurement system based on the results. The background and the purposes of the program and the outline of development subjects are presented.

FCA critical experiment for validation of U capture cross section and experimental analysis

Kugo, Teruhiko; Kitamura, Yasunori; Fukushima, Masahiro; Ando, Masaki; Yamane, Tsuyoshi; Okajima, Shigeaki

no journal, , 

Sodium void reactivity experiments were performed at FCA using uranium fueled core to obtain integral data for evaluation of epithermal capture cross section of U. Experimental analysis were carried out with use of various nuclear data libraries including JENDL-4.0. The ratio of calculated value to experiment value (C/E) are less than unity with JENDL-3.3, ENDF/B-VII.0 and JEFF-3.1. This tendency of C/E values is similar to those for the sodium void reactivity experiments at BFS. Newly obtained integral data at FCA has a large sensitivity to U capture cross section from several hundreds eV to several keV. Thus, the new integral data are useful for validation of epithermal capture cross section of U and are used for the re-evaluation capture cross section of U in subgroup-29 of OECD/NEWA/NSC/WPEC.