Single Molecule Adsorption

We use optically assisted STM to study absorption and intermolecular energy transfer between single quantum dots (QDs) and carbon nanotubes (CNTs). Single PbS, CdSe, CdSe/ZnS, CdSSe/ZnS QDs and CNTs are deposited onto gold, crystalline silicon carbide (c-SiC) and a-SiC surfaces by matrix-assisted dry contact transfer. Adsorbed molecules are excited with modulated laser light and the modulated tunneling current proportional to the optical absorption signal is detected by STM with a lock-in amplifier.