A microscopic picture of surface charge trapping in semiconductor nanocrystals
| Autor: | Jonathan I. Saari, Michael M. Krause, Jonathan Mooney, Patanjali Kambhampati |
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| Rok vydání: | 2013 |
| Předmět: |
Microscopy
Photoluminescence Materials science Luminescence Condensed matter physics Phonon Surface Properties Exciton Temperature General Physics and Astronomy Condensed Matter::Mesoscopic Systems and Quantum Hall Effect Spectrum Analysis Raman Condensed Matter::Materials Science symbols.namesake Nanocrystal Semiconductors Quasiparticle symbols Nanoparticles Surface charge Physical and Theoretical Chemistry Raman spectroscopy Surface states |
| Zdroj: | The Journal of chemical physics. 138(20) |
| ISSN: | 1089-7690 |
| Popis: | Several different compositions of semiconductor nanocrystals are subjected to numerous spectroscopic techniques to elucidate the nature of surface trapping in these systems. We find a consistent temperature-dependent relationship between core and surface photoluminescence intensity and marked differences in electron-phonon coupling for core and surface states based on ultrafast measurements and Resonance Raman studies, respectively. These results support a minimal model of surface charge trapping applicable to a range of nanocrystal systems involving a single surface state in which the trapped charge polarization leads to strong phonon couplings, with transitions between the surface and band edge excitonic states being governed by semiclassical electron-transfer theory. |
| Databáze: | OpenAIRE |
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