7A70.XX Quantum Dots
Concepts
Particle in a box, semiconductor band theory
Overview
Quantum dots of various sizes will fluoresce in different colours when excited by a purple laser pointer. They do not fluoresce when a red laser shines through them.
| Colour | Peak wavelength (nm) | Radius (nm) |
|---|---|---|
| Green | 540 | 2.367454 |
| Yellow | 570 | 2.533894 |
| Orange | 600 | 2.718174 |
| Red | 630 | 2.924941 |
Details
Equipment
- [1] Quantum dot array
- [1] Purple laser pointer
- [1] Red laser pointer
Important Notes
- Lasers can cause blindness. Use with caution.
Script
- Turn off the room lights.
- Using the purple laser pointer, illuminate the quantum dot array from below one cell at a time. The cells should fluoresce in different colours.
- Using the red laser pointer, illuminate the array one cell at a time. The cells should not fluoresce.
Additional Resources
References
- PIRA 7A70.XX
Disclaimer
- Don't attempt this at home!
- SFU is not affiliated with any external sites linked here and is not responsible for their content.
Last revised
- 2025
Technicals
- Original construction: purchased. It is not clear where we bought this, but the University of Michigan has a very similar-looking demo in their video.
Related AV
Related demos
If you have any questions about the demos or notes you would like to add to this page, contact Ricky Chu at ricky_chu AT sfu DOT ca.