1:50 PM–3:02 PM, Saturday, October 24, 2009
Hill Hall - 204
Chair: Thomas Furtak, Colorado School of Mines
Abstract ID: BAPS.2009.4CF.K6.2
2:02 PM–2:14 PM
Jessica Johnston
(University of Utah, Department of Physics and Astronomy)
Eyal Shafran
(University of Utah, Department of Physics and Astronomy)
Ben Mangum
(University of Utah, Department of Physics and Astronomy)
Chun Mu
(University of Utah, Department of Physics and Astronomy)
Jordan Gerton
(University of Utah, Department of Physics and Astronomy)
We investigate optical energy transfer between fluorophores and carbon nanotubes (CNTs). CNTs are grown on Si-oxide wafers by chemical vapor deposition (CVD), lifted off substrates by atomic force microscope (AFM) tips via Van der Waals forces, then shortened by electrical pulses. The tip-attached CNTs are scanned over fluorescent CdSe-ZnS quantum dots (QDs) with sub-nm precision while recording the fluorescence rate. A novel photon counting technique enables us to produce 3D maps of the QD-CNT coupling, revealing nanoscale lateral and vertical features. All CNTs tested ($>$50) strongly quenched the QD fluorescence, apparently independent of chirality. In some data, a delay in the recovery of QD fluorescence following CNT-QD contact was observed, suggesting possible charge transfer in this system. In the future, we will perform time-resolved studies to quantify the rate of energy and charge transfer processes and study the possible differences in fluorescence quenching and nanotube-QD energy transfer when comparing single-walled (SW) versus multi-walled (MW) CNTs, attempting to grow substrates consisting primarily of SW or MWCNTs and characterizing the structure of tip-attached CNTs using optical spectroscopy.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2009.4CF.K6.2