| Project/Area Number |
08044067
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| Research Category |
Grant-in-Aid for international Scientific Research
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| Allocation Type | Single-year Grants |
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| Section | Joint Research |
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| Research Field |
固体物性Ⅰ(光物性・半導体・誘電体)
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| Research Institution | Nagoya University |
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Principal Investigator |
NAKAMURA Arao Nagoya University, Center for Integrated Research in Science and Engineering, Professor, 理工科学総合研究センター, 教授 (50159068)
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| Co-Investigator(Kenkyū-buntansha) |
FABLICE Vallee Ecole Polytechnique, Lab.Quantum Optics, Assistant Professor, ポリテクニク・量子光学研究室, 講師
CHRISTOS Flytzanis Ecole Polytechnique, Lab.Quantum Optics, Professor, ポリテクニク・量子光学研究室, 教授
ICHIDA Masao Nagoya University, Center for Integrated Research in Science and Engineering, Jo, 理工科学総合研究センター, 助手 (30260590)
VALLEE Fabri エコール, ポリテクニク・量子光学研究室, 講師
FLYTZANIS Ch エコール, ポリテクニク・量子光学研究室, 教授
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| Project Period (FY) |
1996 – 1997
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| Project Status |
Completed (Fiscal Year 1997)
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| Budget Amount *help |
¥4,600,000 (Direct Cost: ¥4,600,000)
Fiscal Year 1997: ¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 1996: ¥2,300,000 (Direct Cost: ¥2,300,000)
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| Keywords | Metal nanocrystal / glass composite / Semiconductor nanocrystals / Diluted magnetic semiconductors / Laser ablation technique / Pump and probe spectroscopy / Nonlinear optical response / Hot electrons / レーザーアプレーション / 銀ナノ結晶 / 半磁性半導体超微粒子 / 非線形光学 |
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| Research Abstract |
We have studied nonlinear optical properties of nanostructured materials to investigate a guiding principle for development of photonic device materials. Exchanging the researchers in French and Japanese teams, we performed experiments and discussed to get mutual understanding of this study. In silver nanocrystal/glass composites, we investigated the nonlinear response in a femtosecond time region with different excitation conditions : surface plasmon, interband (Nagoya University) and intraband (Ecole polytechnique) excitations. we have found that the nonlinear response with a reponse time of a few ps is originated from hot electron effects and nonlinear refractive index is negative. For less than 200 fs, the electron system does not show the Fermi distribution because the system is not in equilibrium. Furthermore, we have observed oscillation behaviors in nonlinear response due to ballistic phonon scattering. In diluted magnetic semiconductors, we have succeeded to fabricate CdMnTe nanocrystals with a diameter of 12 nm by means of the laser ablation technique. In CuCl nanocrystals we have observed quantum beat phenomena due to the quantum interference between exciton and biexciton states and the interference between the zero-phonon and LO phonon assisted transition of confined excitons. Furthermore, we have observed, for the first time, the memory effect of the reservoir, ie. the non-Markovian phase relaxation of confined excitons since acoustic phonons are confined. Finally, we have found the the enhancement of third-order susceptibilities in copper halide nanocrystals is originated from the giant oscillator strength effect, and the two-exciton state and the multiexciton states due to the valence band structure play an important role in nonlinear susceptibilities at the exciton resonance in the large size region. These results give us a guiding principle to develop nonlinear optical materials on the nanometer scale.
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