3:45–4:45 pm GCIS W301
Infrared Conducting Colloidal Quantum Dots Inks. Our idea factory.
The 3-5 microns atmospheric window is useful for thermal imaging and molecular sensing. It is dominated by epitaxial II-VI and III-V semiconductors and inaccessible to solution processed organics. Making colloidal quantum dots (CQD) inks for these thermal photons has been a long-term goal of my lab. To get there, we invented methods to create electronic infrared absorptions, to dope carriers, to slow down electronic relaxation, and to make conductive CQD films. Mercury based CQDs have now shown emission and background limited detection, promising a dramatically lower cost mid-infrared technology. This is offset by a lower performance which improves rapidly. Further progress will come with brighter emission, which may not be intuitive for a detector material, while increasing absorption and conduction will also help. We currently work on perfecting QD sizes and interfaces for emission and transport studies, and on microfabrication to increase optical coupling. Future work will rely on the intraband transitions of semiconductors without heavy metals (Hg,Cd,Pb).
