Nanoscale fluorescence imaging with quantum dot near-field electroluminescence
Abstract
We demonstrate near-field fluorescence excitation and imaging with a quantum dot (QD) light emitting diode (QDLED) integrated at the tip of a scanning probe. The tip-embedded QDLED is employed in a near-field scanning optical microscopy setup to directly excite a secondary colloidal QD sample. Electrically pumped QDs enable multi-color, self-illuminating probes with no conventional optics needed for light coupling. Monolayer QDs stamped at the very tip of a micromachined silicon probe facilitates precise position control of the ultra-thin (10-15 nm) light source. Sensitivity of fluorescence intensity to the QDLED-QD sample distance was measured down to 50 nm order, demonstrating spatially resolved imaging.
- Publication:
-
Applied Physics Letters
- Pub Date:
- July 2012
- DOI:
- 10.1063/1.4739235
- Bibcode:
- 2012ApPhL.101d3118H
- Keywords:
-
- cadmium compounds;
- colloids;
- electroluminescence;
- fluorescence;
- II-VI semiconductors;
- light emitting diodes;
- micromachining;
- monolayers;
- nanostructured materials;
- optical microscopy;
- semiconductor quantum dots;
- zinc compounds;
- 78.60.Fi;
- 78.67.Hc;
- 85.60.Jb;
- 68.65.Hb;
- 78.55.Et;
- Electroluminescence;
- Quantum dots;
- Light-emitting devices;
- Quantum dots;
- II-VI semiconductors