Colloidal QDs offer a potential combination second to none of tunable materials properties and a suitability for solution-based processing. The underlying challenge is to turn QDs into a mature material platform and realize their full potential for nanophotonic devices. It requires QDs with the right properties, a processing technology to combine QDs with integrated photonics platforms and simulation and characterization of devices, all in the context of an emerging field that actively transfers scientific findings to the market.
A number of recent breakthroughs have made QDs ready to become an active optical material in even the most advanced nanophotonics devices. We demonstrated the formation of nanoplatelets with emission linewidths as narrow as 5-10 nm. We also found that blinking in the emission of single QDs could be eliminated by growing thick, alloyed shells, and also showed how wavefunction engineering by shell growth reduces exciton relaxation and dephasing in QDs. In addition, we recently discovered that nearly thresholdless, long lived optical amplification is possible when QDs are turned into effective 3-level systems.
Phonsi aims at building on these findings to synthesize QDs that exhibit non-blinking, highly efficient single photon emission or nearly thresholdless gain over a much broader wavelength range then currently demonstrated in the literature with a focus on heavy metal free materials. This brings phonsi at the forefront of developments in QD synthesis and it will make possible applications of QDs in integrated nanolasers and single photon sources.
Importantly, phonsi is not an isolated programme. Its focus on nanomaterials, solution-based processing and integration in nanophotonics devices is closely linked to various running research initiatives. Phonsi uniquely brings together research from different viewpoints, ranging from fundamental science to the business perspective, different domains, from chemistry to physics to engineering, and different methodologies, from material synthesis to analysis of properties and devices to simulation and modeling in a single project supported by some of the most outstanding researchers in the field. This offers a fertile, supradisciplinary training environment at the cross-roads of nanomaterials and nanophotonics for maximum impact.
