- 著者
- Siribunbandal Papaorn Yamaguchi Shigeki Kojima Kenichi Fukuda Junji Suzuki Hiroaki
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.95, no.20, pp.204105, 2009-11
- 被引用文献数
- 10 9
Autonomous control of the transport of solutions in microfabricated flow channels using electrowetting-based valves and integrated electrochemical cells is proposed. An electrowetting-based valve formed with a gold electrode was opened when an electrolyte solution reached a zinc electrode in a controlling flow channel and a potential was applied to the gold electrode, causing the transport of the solution in the flow channel. Independent composite electrodes consisting of gold and zinc could function in the same manner without requiring additional electrodes. Controlled autonomous transport of solutions in a network of flow channels could also be carried out using the integrated valves.
- 著者
- Narahara A. Ito K. Suemasu T. Takahashi Y. K. Ranajikanth A. Hono K.
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.94, no.20, pp.202502, 2009-05
- 被引用文献数
- 62 29
The spin polarization of (100)-oriented gamma[prime]-Fe4N layers grown on MgO(001) substrates by molecular beam epitaxy was deduced from point contact Andreev reflection measurements, and the value was compared with that of alpha-Fe. The spin polarization (P) for gamma[prime]-Fe4N is approximately 0.59 at 7.8 K. This value is distinctly larger than that for alpha-Fe (P=0.49 at 7.8 K) measured with an identical setting. The mechanism of enhanced spin polarization in gamma[prime]-Fe4N is discussed.
- 著者
- Sato Hiroki
- 出版者
- 東京大学大学院新領域創成科学研究科基盤科学研究系物質系専攻
- 巻号頁・発行日
- 2011-03-24
報告番号: ; 学位授与年月日: 2011-03-24 ; 学位の種別: 修士 ; 学位の種類: 修士(科学) ; 学位記番号: 修創域第3678号 ; 研究科・専攻: 新領域創成科学研究科基盤科学研究系物質系専攻
1 0 0 0 OA 資本循環と資本類型―経済政策類型論の構築のために―
- 著者
- 渡邉 尚
- 出版者
- 京都大學經濟學會
- 雑誌
- 經濟論叢 (ISSN:00130273)
- 巻号頁・発行日
- vol.157, no.1, pp.1-28, 1996-01
1 0 0 0 OA 性格自己診断検査の作製
- 著者
- 矢田部 達郎
- 出版者
- 京都大學文學部
- 雑誌
- 京都大學文學部研究紀要 (ISSN:04529774)
- 巻号頁・発行日
- vol.3, pp.71-167, 1954-03-30
この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました。
1 0 0 0 OA ウナギ仔魚輸送に関わる北赤道海流における海洋構造の季節的・経年的変動に関する研究
- 著者
- 銭本 慧
- 出版者
- 新領域創成科学研究科 環境学研究系 自然環境学専攻
- 巻号頁・発行日
- 2008-03-24
報告番号: ; 学位授与年月日: 2008-03-24 ; 学位の種別: 修士 ; 学位の種類: 修士(環境学) ; 学位記番号: 修創域第2586号 ; 研究科・専攻: 新領域創成科学研究科自然環境学専攻
- 著者
- Ahart Muhtar Hushur Anwar Bing Yonghong Ye Zuo-Guang Hemley Russell J. Kojima Seiji
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.94, no.14, pp.142906, 2009-04
- 被引用文献数
- 27
Brillouin spectroscopy of Pb(Sc0.5Nb0.5)O3 single crystals reveals an order-disorder ferroelectric phase transition occurs at 110 °C upon cooling. A softening of the longitudinal acoustic (LA) mode is observed that can be attributed to the coupling between polar nanoregions and acoustic modes. A critical slowing down of the central peak, a feature of order-disorder ferroelectric phase transitions, is observed near Tc. The similarity in temperature dependences of the two kinds of relaxation times determined from the central peak and LA mode suggests that the changes in the central peak arise from local polarization fluctuations in the polar nanoregions.
- 著者
- Tanaka Hisaaki Watanabe Shun-ichiro Ito Hiroshi Marumoto Kazuhiro Kuroda Shin-ichi
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.94, no.10, pp.103308, 2009-03
- 被引用文献数
- 33 17
Charge carrier concentration in operating field-effect transistor (FET) of regioregular poly(3-hexylthiophene) has been directly determined by electron spin resonance (ESR). ESR signals of field-induced polarons are observed around g=2.003 under the application of negative gate-source voltage (Vgs). Upon applying drain-source voltage (Vds), ESR intensity decreases linearly in the low Vds region, reaching to about 50% of the initial intensity at the pinch-off point (Vds~=Vgs). For larger absolute values of Vds, it becomes nearly Vds independent. These behaviors are well explained by the change in the carrier concentration obtained by the FET theory using gradual channel approximation.
- 著者
- Kita Yuki Yoshida Shinichi Hosoi Takuji Shimura Takayoshi Shiraishi Kenji Nara Yasuo Yamada Keisaku Watanabe Heiji
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.94, no.12, pp.122905, 2009-03
- 被引用文献数
- 8 8
Change in the work function (WF) of the gate electrode material caused by the contact with Hf-based high-k gate dielectrics was investigated by means of the flat-band voltage (Vfb) shift in capacitance-voltage curves, and the interface dipole, which modifies the WF, was characterized by x-ray photoelectron spectroscopy. We observed a negative Vfb shift and corresponding interface dipole, which suggest the formation of oxygen vacancy (VO) in the Hf-based oxides. In contrast, we observed an opposite (positive) Vfb shift and interface dipole when Au electrodes were formed on cleaned Hf-based dielectrics. This indicates that Au–Hf bond hybridization at the Au/HfSiON interface also causes effective WF modulation, as theoretically predicted by Shiraishi et al. (Tech. - Dig. Int. Electron Devices Meet. 2005, 43).
- 著者
- Moritomo Y. Nakada F. Kurihara Y.
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.94, no.11, pp.111914, 2009-03
- 被引用文献数
- 5 4
Electrochromism is extensively investigated for practical application of display and memory devices. To develop the material, reliable information on the optical and electronic properties of the solid film is indispensable. Here, we propose valence-differential spectroscopy that can selectively extract the spectral components related to the oxidized/reduced metal site. We applied the spectroscopy to Co2+–Fe2+delta and Co2+delta–Fe2+ cyanide films with finely control of averaged valence (delta) of the transition metal by external electric pulses. The spectroscopy revealed transition energy E, width Gamma, and oscillator strength f of the spectral components related to the transition metal.
- 著者
- Hase Muneaki
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.94, no.11, pp.112111, 2009-03
- 被引用文献数
- 18 6
Ultrafast dephasing of the plasmonlike longitudinal optical phonon-plasmon coupled (LOPC) mode in highly doped n-GaAs has been investigated by using a femtosecond optical pump-probe technique with 40 THz bandwidth as a function of photodoping levels. The direct measurement of plasmon damping with the help of a wavelet analysis enables us to extract carrier (electron) mobility, which decreases with increasing the photodoping levels. It is found that the mobility is suppressed at high photodoping levels due to electron-hole scattering, while it is enhanced near a critical density, being plausibly attributed to the strong coherent coupling of the LO phonon with the plasmon.
- 著者
- Xu Maojie Okada Arifumi Yoshida Shoji Shigekawa Hidemi
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.94, no.7, pp.073109, 2009
- 被引用文献数
- 5 7
Methods of forming various In nanostructures on Si surfaces are demonstrated. Using a high-index Si(311) surface, isolated nanotriangles and wires were grown by optimizing the deposition rate and substrate temperature. In contrast, nanodots were formed by the deposition of In on a Si(111)-In-31×31 surface at room temperature (RT) deposition. On a Si(111)-In-4×1/31×31 coexisting surface, nanowires were selectively grown in the Si(111)-In 4×1 area by RT deposition through the nucleation promoted by the boundary barrier produced by the surrounding 31×31 area. Details were studied using scanning tunneling microscopy.
- 著者
- Fukata N. Mitome M. Bando Y. Seoka M. Matsushita S. Murakami K. Chen J. Sekiguchi T.
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.93, no.20, pp.203106, 2008-11
- 被引用文献数
- 33 20
Codoping of boron (B) and phosphorus (P) atoms was performed during the synthesis of silicon nanowires (SiNWs) by laser ablation. The observation of a local vibrational mode of B clearly showed B doping in codoped SiNWs, while Fano broadening due to heavy B doping disappeared, indicating compensation by P donors. The electrospin resonance signal of conduction electrons also disappeared due to compensation by B acceptors. These results indicate that codoping of B and P atoms was achieved in SiNWs during laser ablation.
- 著者
- Tanimoto H. Yamada K. Mizubayashi H. Matsumoto Y. Naramaoto H. Sakai S.
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.93, no.15, pp.151919, 2008-10
- 被引用文献数
- 7
C60 films with thicknesses of 100–480 nm were deposited on Si reed substrates under in situ photoirradiation. In anelasticity measurements, no internal friction peaks associated with rotational motions of the C60 molecules were observed, and Young's modulus was 1.5 times larger than that of a pristine C60 material. X-ray diffraction patterns suggested that the face-centered cubic lattice was contracted by about 3% and locally distorted from the pristine C60 material. Raman spectra very similar to those reported for dimerized C60 were also obtained. These characteristics recovered to those of the pristine C60 materials after annealing the C60 films at 523 K. These results indicate uniform dimerization in C60 films deposited under in situ photoirradiation.
- 著者
- Ko J.-H. Kojima S. Koo T.-Y. Jung J. H. Won C. J. Hur N. J.
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.93, no.10, pp.102905, 2008-09
- 被引用文献数
- 69 45
A strong relaxation mode was observed in the paraelectric phase of barium titanate (BaTiO3) single crystals by Brillouin scattering study and was found to correlate with the softening of the longitudinal acoustic mode and the increase in the hypersonic damping. These observations support the existence of polar percursors and their electrostrictive coupling with the strain caused by the acoustic waves, consistent with former studies evidencing off-centered Ti ions in the high-symmetry cubic phase. A critical slowing down has been clearly observed in the vicinity of the cubic-tetragonal phase transition, indicating order-disorder component contributes to the phase transition of BaTiO3.
- 著者
- Chong S. V. Kadowaki K. Xia J. Idriss H.
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.92, no.23, pp.232502, 2008-06
- 被引用文献数
- 34
The magnetic behavior of titanium dioxide nanobelts has been investigated with and without Codoping. Room temperature ferromagnetism was observed when the Co-doped anatase TiO2nanobelts were prepared via vacuum annealing of 2.5 at. % Co-doped titanate nanobelts, whileannealing them in air resulted in paramagnetic ordering. Interestingly, by vacuum annealing theundoped titanate nanobelts under the same conditions, superparamagnetic ordering was observed inthe resulting anatase TiO2 nanobelts. The electron paramagnetic resonance of this latter sampleshows a strong symmetrical signal at g=2.003 suggesting some sort of exchange interactions amongthe localized electrons’ spin moments from single electron trapped in oxygen vacancies.
- 著者
- Ootsuka Teruhisa Suemasu Takashi Chen Jun Sekiguchi Takashi Hara Yoshiaki
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.92, no.19, pp.192114, 2008-05
- 被引用文献数
- 14
We have evaluated the lifetime and diffusion length of photogenerated minority carriers (holes) in single-crystalline n-type beta-FeSi2 bulk grown by chemical vapor transport. The diffusion length measured by optical-beam-induced current agreed well with that measured by electron-beam-induced current, that is, 51 and 38 µm, respectively, for samples annealed at 800 °C for 8 h. The decay curve of photoconductivity obtained by 1.31 and 1.55 µm light pulses was well fitted by assuming a carrier lifetime of approximately a few microseconds. The mobility of photogenerated minority carriers was estimated to be approximately 200–360 cm2/V s from the measured lifetime and diffusion length.
- 著者
- Uchida Noriyuki Mikami Youhei Kintoh Hiroshi Murakami Kouichi Fukata Naoki Mitome Masanori Hase Muneaki Kitajima Masahiro
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.92, no.15, pp.153112, 2008-04
- 被引用文献数
- 5
We have developed a robust method for fabricating Si nanoregions in silica glass using femtosecond laser processing. We attained a vivid formation of silicon-rich nanoregions site-selectively generated in SiO2 by irradiation of femtosecond laser pulses to the interface of a SiO2 substrate and deposited aluminum (Al) thin film, where the Al element acts as a gettering site for O atoms. Growth of high-density Si nanocrystals and amorphous Si was observed by transmission electron microscopy in the region that was multiply irradiated with the femtosecond laser. Furthermore, local annealing with a cw laser enhances the Si nanocrystal growth, which was determined by micro-Raman measurements.
- 著者
- Moritomo Y. Nakada F. Kamioka H. Kim J. E. Takata M.
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.92, no.14, pp.141907, 2008-04
- 被引用文献数
- 4 4
The guest-host interaction is one of the promising tools to control the material state. Here, we found that a cyano-bridged compound Na0.50Co[Fe(CN)6]0.723.8H2O shows a first-order structural phase transition below a critical pressure Pc (150 Pa) at 300 K. Judging from suppression of the OH stretching mode in the infrared spectra, we ascribed the phase transition to desorption of the ligand waters. The phase transition accompanies a significant change of the visible absorption spectra, reflecting the strong hybridization between the Co eg state and the CNσ states.
- 著者
- Ootsuka Teruhisa Suemasu Takashi Chen Jun Sekiguchi Takashi
- 出版者
- American Institute of Physics
- 雑誌
- APPLIED PHYSICS LETTERS (ISSN:00036951)
- 巻号頁・発行日
- vol.92, no.4, pp.042117, 2008-01
- 被引用文献数
- 13 15
We have evaluated the diffusion length of minority carriers (holes) in single-crystalline n-type beta-FeSi2 bulk grown by chemical vapor transport by means of electron-beam-induced current (EBIC) technique in the edge-scan configuration. The EBIC line-scan data showed a clear exponential dependence of distance from the Al electrode. The diffusion length was estimated to be 20 µm at room temperature, and increased upon high-temperature annealing, reaching approximately 30 µm after annealing at 800 °C for 8 h. This result explained the improvement of photoresponsivity in the Al/n-beta-FeSi2 Schottky diodes by high-temperature annealing.