Fluorescence Enhancement in Non-Contact and Dynamic-Force Apertureless Near-Field Scanning Optical Microscopy
V V. Protasenko, Alan Gallagher, David Nesbitt
The fluorescence of single ZnS overcoated CdSe Quantum dots (QDS) and dye doped polystyrene spheres (PSs) embedded in the evanescent optical field has been studied using an apertureless near-field scanning optical microscope (ANSOM) operating in non-contact and dynamic-force modes. The fluorescence intensity of an individual ZD can be enhanced 5 times when an HF etch-cleaned Si probe is located over the QD and spatially resolved with 30 nm full width at half maximum when the ANSOM is operating in non-contact mode. Furthermore, we show that the fluorescence contrast in ANSOM is typically 5 times greater than the above enhancement coefficient. In the case of ANSOM dynamic-force mode, the fluorescence of QDs and PSs depends on the pressure applied by the probe to the sample.
Nanoscale Optics and Applications, Conference | | Nanoscale Optics and Applications | SPIE
July 1, 2002
Proceedings of SPIE--the International Society for Optical Engineering
, Gallagher, A.
and Nesbitt, D.
Fluorescence Enhancement in Non-Contact and Dynamic-Force Apertureless Near-Field Scanning Optical Microscopy, Nanoscale Optics and Applications, Conference | | Nanoscale Optics and Applications | SPIE, Undefined
(Accessed March 2, 2024)