2007 Fiscal Year Final Research Report Summary
Surface enhance Raman scattering in aligned metal/semiconductor nanocrystals
| Project/Area Number |
18540319
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Condensed matter physics I
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| Research Institution | Nara Institute of Science and Technology |
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Principal Investigator |
YAMAMOTO Aishi Nara Institute of Science and Technology, Graduate School of Materials Science, Associate Professor (10261546)
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| Co-Investigator(Kenkyū-buntansha) |
ISHIZUMI Atsushi Nara Institute of Science and Technology, Graduate School of Materials Science, Assistant Professor (10346314)
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| Project Period (FY) |
2006 – 2007
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| Keywords | Raman scattering / photoluminescence / semiconductor nanocrystals / surface plasmon / absorption spectra |
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| Research Abstract |
We studied electronic interaction between semiconductor nanocrystals and metal nanocrystals by measuring Raman scattering and photoluminescence spectra. First, we discussed Raman scattering spectral shape of semiconductor nanocrystals. The Raman scattering spectral shape was calculated by a phonon confinement model considering the relaxation of the momentum conservation rule. The semiconductor nanocrystals we used had a possibility to farm zincblende or wurtzite crystal structure. The calculated Raman scattering spectra assuming wurtzite structure were more preferable to explain the experimental spectra. This result was consistent with the crystal structure obtained from TEM images. Our finding indicates that we can determine the nanocrystal structure from the Raman scattering analyses without using e. g. TEM.
Next, we fabricated close-packed semiconductor/metal mixed nanoparticle monolayers and measured the Raman scattering and photoluminescence spectra simultaneously, in order to inve
… More
stigate the influence of the Raman scattering and photoluminescence properties of semiconductor nanoparticles on the surface plasmons of metal nanoparticles. The TEM images showed that close-packed semiconductor/metal nanoparticle monolayers were successfully fabricated. With an increase of the metal nanoparticle ratio, the PL intensity decreased dramatically, while the Raman scattering intensity increased slightly. The time-resolved photoluminescence spectra showed that the photo-excited exciton energy in semiconductor nanocrystals transferred to metal nanoparticles. The observed semiconductor-nanoparticle number density dependences of the Raman scattering and photoluminescence intensities were able to be explained by an energy transfer model which considered the effects of electromagnetic enhancement and energy transfer. We demonstrated that conducting simultaneous measurements of Raman scattering and photoluminescence spectra is a useful technique to understand the interaction between metal and semiconductor nanostructures. Less
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Research Products
(26 results)
