Mechanism of photoluminescence enhancement in single semiconductor nanocrystals on metal surfaces

Self-assembled metal–semiconductor compound nanocrystals on Group IV semiconductor surfaces

Nanocrystals of material B may form on a substrate of material A in order to relieve the strain from the B/A crystalline mismatch. In the most simplistic approximation, if such an elastic relaxation outweighs the additional surface energy due to the island walls, it will create the thermodynamic tendency for the nanocrystal formation. Hence one can ‘engineer’ ultra-small and crystallographicall...

Fluorescence decay time of single semiconductor nanocrystals.

We present fluorescence decay measurements of single ZnS covered CdSe nanocrystals. It is shown that the fluorescence decay time is fluctuating during the investigation leading to a multiexponential decay even for a single nanocrystal. In combination with measurements of the fluorescence blinking behavior we find that a high fluorescence intensity is correlated with a long fluorescence decay ti...

Atomic-scale Modeling of Transition-metal Doping of Semiconductor Nanocrystals

Single-sized colloidal CdTe nanocrystals with strong bandgap photoluminescence.

One brand-new colloidal ensemble of single-sized CdTe nanocrystals, exhibiting a sharp first excitonic absorption peak at 427 nm and bright bandgap photoluminescence at 427 nm with narrow full width at half maximum (FWHM) of only ca. 10 nm, was synthesized in 1-octadecene (ODE) via a non-injection one-pot approach which features high synthetic reproducibility with potential for industrial scale...

Single-molecule chemistry of metal phthalocyanine on noble metal surfaces.

To develop new functional materials and nanoscale electronics, researchers would like to accurately describe and precisely control the quantum state of a single molecule on a surface. Scanning tunneling microscopy (STM), combined with first-principles simulations, provides a powerful technique for acquiring this level of understanding. Traditionally, metal phthalocyanine (MPc) molecules, compos...