Periodic Reporting for period 4 - FORWARD (New Frontiers for Optoelectronics with Artificial Media)
Reporting period: 2023-05-01 to 2024-10-31
To detect or generate complex light beams that are increasingly needed in biology and photonics (light with non-zero angular momentum and non-classical light), it is necessary to rely on bulky and sophisticated setups, considerably limiting their potential. The FORWARD project aims at obtaining the same functionalities with a new generation of optoelectronic components of submicron thickness in the near infrared range. This ambitious objective implies to devise radically new ways of creating and manipulating complex light at the nanoscale. In FORWARD, this tremendous challenge will be addressed by hybridizing two classes of artificial media—colloidal quantum dots (CQDs) and metamaterials—and leveraging advanced cooperative behaviours within the hybrids. In the new devices, which will be pumped electrically, the active layers will be made of a film of CQDs interwoven with the metallic inclusions of an optical metamaterial.
FORWARD has a strong multidisciplinary character as it lies at the crossroads of nanocrystal processing, nanofabrication, nanophotonics, condensed matter physics and optoelectronics. FORWARD is organized around three research thrusts: (i) unravelling and leveraging the transport properties in metamaterial/CQD hybrids and developing metamaterial/ CQD photodetectors demonstrating the advantage of the hybridization. (ii) inducing classical cooperative effects between the different metamaterial inclusions and following this approach to fabricate hybrids LEDs capable of emitting optical vortices. (iii) inducing collective synchronizations among the CQDs and demonstrate hybrids LEDs that produce coherent and non-classical light.
FORWARD has a strong multidisciplinary character as it lies at the crossroads of nanocrystal processing, nanofabrication, nanophotonics, condensed matter physics and optoelectronics. FORWARD is organized around three research thrusts: (i) unravelling and leveraging the transport properties in metamaterial/CQD hybrids and developing metamaterial/ CQD photodetectors demonstrating the advantage of the hybridization. (ii) inducing classical cooperative effects between the different metamaterial inclusions and following this approach to fabricate hybrids LEDs capable of emitting optical vortices. (iii) inducing collective synchronizations among the CQDs and demonstrate hybrids LEDs that produce coherent and non-classical light.
FORWARD has 3 research thrusts.
The first thrust aims at unravelling the optoelectronic properties of artificial media hybridizing colloidal quantum dots (CQDs) and optical metamaterials. We have shown that the behaviour of the CQDs are governed by a thermalization of their carriers (DOI: 10.1021/acs.jpclett.1c01206). Next, we have used this knowledge to maximize the interactions between the CQDs and metamaterials (DOI: 10.1021/acs.nanolett.1c03865). We then showed that thermalization occurs as result of mutual coupling between neighboring quantum dots via Förster Resonance Energy Transfer (DOI: 10.1021/acsphotonics.3c01232). A spectacular consequence of these interactions is that the emitter’s lifetime is essentially independent of the photonic environment—in contradiction with textbook literature. Finally, we have developed new sensors and photovoltatic devices that leverage our findings (results still unpublished due to pending IP application).
The 2nd thrust aimed at creating LEDs emitting optical vortex beams. The key challenge is that the formation of vortices requires coherence properties that are possessed by lasers—but not by LEDs that emit incoherent light by spontaneous emission. To solve this problem, we have experimentally implemented CQD/metamaterial hybrids with extended spatial coherence (DOI: 10.1103/PhysRevApplied.14.064077). Second, we have demonstrated the photoluminescence of composite vector beams (DOI: 10.1063/5.0065486). Last, we have demonstrated vortex-emitting LEDs (results under peer review). The expertise developed has also been applied to characterize other beams generated by the interaction of CQDs and photonic structures (DOI: 10.1021/acs.jpcc.3c04126 10.1002/adfm.202403532 10.1002/adom.202300863 10.1002/adom.202401601 10.1002/adom.202402747). The specific knowledge on optical vortex beams, both in design and characterization, has also been applied to nonlinear optics in collaboration with people specialized in this field (DOI: 10.1038/s41467-024-45607-2 10.1038/s41377-025-01741-0).
The last thrust aims at achieving coherent emission through the synchronization of the CQDs. The knowledge acquired in the previous thrusts made us decide to reach this goal through plasmonic Bose-Einstein condensation. We have designed and tested cavities allowing plasmon thermalization—a key requisite for thermalization. We are currently finalizing the measurements to disseminate these findings.
The first thrust aims at unravelling the optoelectronic properties of artificial media hybridizing colloidal quantum dots (CQDs) and optical metamaterials. We have shown that the behaviour of the CQDs are governed by a thermalization of their carriers (DOI: 10.1021/acs.jpclett.1c01206). Next, we have used this knowledge to maximize the interactions between the CQDs and metamaterials (DOI: 10.1021/acs.nanolett.1c03865). We then showed that thermalization occurs as result of mutual coupling between neighboring quantum dots via Förster Resonance Energy Transfer (DOI: 10.1021/acsphotonics.3c01232). A spectacular consequence of these interactions is that the emitter’s lifetime is essentially independent of the photonic environment—in contradiction with textbook literature. Finally, we have developed new sensors and photovoltatic devices that leverage our findings (results still unpublished due to pending IP application).
The 2nd thrust aimed at creating LEDs emitting optical vortex beams. The key challenge is that the formation of vortices requires coherence properties that are possessed by lasers—but not by LEDs that emit incoherent light by spontaneous emission. To solve this problem, we have experimentally implemented CQD/metamaterial hybrids with extended spatial coherence (DOI: 10.1103/PhysRevApplied.14.064077). Second, we have demonstrated the photoluminescence of composite vector beams (DOI: 10.1063/5.0065486). Last, we have demonstrated vortex-emitting LEDs (results under peer review). The expertise developed has also been applied to characterize other beams generated by the interaction of CQDs and photonic structures (DOI: 10.1021/acs.jpcc.3c04126 10.1002/adfm.202403532 10.1002/adom.202300863 10.1002/adom.202401601 10.1002/adom.202402747). The specific knowledge on optical vortex beams, both in design and characterization, has also been applied to nonlinear optics in collaboration with people specialized in this field (DOI: 10.1038/s41467-024-45607-2 10.1038/s41377-025-01741-0).
The last thrust aims at achieving coherent emission through the synchronization of the CQDs. The knowledge acquired in the previous thrusts made us decide to reach this goal through plasmonic Bose-Einstein condensation. We have designed and tested cavities allowing plasmon thermalization—a key requisite for thermalization. We are currently finalizing the measurements to disseminate these findings.
Achievement #1: New photovoltaic effect arising from engineering the carrier properties in CQDs hybridized in optical metasurfaces (nothing published yet due to pending intellectual property application). Preliminary results have allowed the PI to win a follow up ERC PoC grant (AMELI project).
Achievement #2: Experimental demonstration of the spontaneous emission of optical vortex beams, both in photoluminescence (DOI: 10.1103/PhysRevApplied.14.064077 and 10.1063/5.0065486) and electroluminescence (main breakthrough currently under peer review).
Achievement #3: Identification of two carrier thermalization regimes within assemblies of CQDs, allowing a unified understanding of their transport and luminescent properties (DOI: 10.1021/acs.jpclett.1c01206)
Achievement #4: Experimental discovery of a “phase transition” in periodic arrays of metallic nanoparticles, with the apparition of electromagnetically induced absorption (EIA) for highly subwavelength structures (DOI: 10.1021/acs.nanolett.1c03865).
Achievement #5: Discovery that carrier lifetimes are essentially independent of the photonic environment surrounding layers of CQDs, in contradiction to standard textbook theory (DOI: 10.1021/acsphotonics.3c01232).
Note that other achievements related to the third research thrust of FORWARD are nearly completed but not yet finalized.
Achievement #2: Experimental demonstration of the spontaneous emission of optical vortex beams, both in photoluminescence (DOI: 10.1103/PhysRevApplied.14.064077 and 10.1063/5.0065486) and electroluminescence (main breakthrough currently under peer review).
Achievement #3: Identification of two carrier thermalization regimes within assemblies of CQDs, allowing a unified understanding of their transport and luminescent properties (DOI: 10.1021/acs.jpclett.1c01206)
Achievement #4: Experimental discovery of a “phase transition” in periodic arrays of metallic nanoparticles, with the apparition of electromagnetically induced absorption (EIA) for highly subwavelength structures (DOI: 10.1021/acs.nanolett.1c03865).
Achievement #5: Discovery that carrier lifetimes are essentially independent of the photonic environment surrounding layers of CQDs, in contradiction to standard textbook theory (DOI: 10.1021/acsphotonics.3c01232).
Note that other achievements related to the third research thrust of FORWARD are nearly completed but not yet finalized.