High pressure photoluminescence and Raman investigations of CdSe∕ZnS core/shell quantum dots
- 8 January 2007
- journal article
- research article
- Published by AIP Publishing in Applied Physics Letters
- Vol. 90 (2) , 021921
- https://doi.org/10.1063/1.2430772
Abstract
Photoluminescence(PL) and Raman spectroscopies of Cd Se ∕ Zn S core/shell quantum dots(QDs) were studied under hydrostatic pressure ( 0 – 160 kbars ) at room temperature. Two phase transitions, at 69 and 79 kbars , respectively, were observed, which correspond to wurtzite-rocksalt and rocksalt-cinnabar structural transformations. The full width at half maximum of PL peaks was found to decrease anomalously approximately 30% with pressure. These experimental data show significant difference between the Cd Se ∕ Zn S core/shell QDs and simple bare CdSeQDs or bulk CdSe, implying the ZnS shell plays a dominant role in structural stability and electronic state of such system.Keywords
This publication has 16 references indexed in Scilit:
- Demonstration of a nanoparticle-based optical diodeOptics Letters, 2006
- From nano-optics to street lightsNature Materials, 2004
- Effect of ZnS shell thickness on the phonon spectra in CdSe quantum dotsPhysical Review B, 2003
- Electrical properties and phase transition of CoFe2O4 nanocrystals under pressureJournal of Applied Physics, 2003
- Individual mesoscopic structures studied with sub-micrometer optical detection techniques: CdSe nanocrystals capped with TOPO and ZnS-overcoated systemJournal of Luminescence, 2002
- Pressure-induced electronic coupling in CdSe semiconductor quantum dotsPhysical Review B, 2002
- Self-Assembly of CdSe−ZnS Quantum Dot Bioconjugates Using an Engineered Recombinant ProteinJournal of the American Chemical Society, 2000
- Phase transformation and conductivity in nanocrystal PbS under pressureJournal of Applied Physics, 2000
- (CdSe)ZnS Core−Shell Quantum Dots: Synthesis and Characterization of a Size Series of Highly Luminescent NanocrystallitesThe Journal of Physical Chemistry B, 1997
- Size Dependence of a First Order Solid-Solid Phase Transition: The Wurtzite to Rock Salt Transformation in CdSe NanocrystalsScience, 1994