- Author
- Year
- 2010
- Title
- Red spectral shift and enhanced quantum efficiency in phonon-free photoluminescence from silicon nanocrystals
- Journal
- Nature Nanotechnology
- Volume | Issue number
- 5 | 12
- Pages (from-to)
- 878-884
- Document type
- Article
- Faculty
- Faculty of Science (FNWI)
- Institute
- Van der Waals-Zeeman Institute (WZI)
Van 't Hoff Institute for Molecular Sciences (HIMS) - Abstract
-
Crystalline silicon is the most important semiconductor material in the electronics industry. However, silicon has poor optical properties because of its indirect bandgap, which prevents the efficient emission and absorption of light. The energy structure of silicon can be manipulated through quantum confinement effects, and the excitonic emission from silicon nanocrystals increases in intensity and shifts to shorter wavelengths (a blueshift) as the size of the nanocrystals is reduced. Here we report experimental evidence for a short-lived visible band in the photoluminescence spectrum of silicon nanocrystals that increases in intensity and shifts to longer wavelengths (a redshift) with smaller nanocrystal sizes. This higher intensity indicates an increased quantum efficiency, which for 2.5-nm-diameter nanocrystals is enhanced by three orders of magnitude compared to bulk silicon. We assign this band to the radiative recombination of non-equilibrium electron-hole pairs in a process that does not involve phonons.
- URL
- go to publisher's site
- Link
- Link
- Language
- English
- Persistent Identifier
- https://hdl.handle.net/11245/1.331742
Disclaimer/Complaints regulations
If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library, or send a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible.