Periodic Reporting for period 4 - COINFLIP (Coupled Organic Inorganic Nanostructures for Fast, Light-Induced Data Processing)
Berichtszeitraum: 2023-08-01 bis 2024-07-31
COINFLIP seeks to make faster optical transceivers, which are crucial for every modern data-communication network, where they convert in-coming optical data from an optical fiber into electrical information to be processed by a computer end station. A central problem in this respect is that materials for processing optical data input must find a compromise between speed and sensitivity. In simple words, a material cannot be fast and sensitive to an incoming signal simultaneously because registering a very weak stimulus requires some time to process it. Therefore, COINFLIP merges one material, which is only fast, with a second material that is very sensitive (and slow). With this approach, we have developed materials that could convert light into electric information with a frequency of 0.23 GHz using an energy of only 27 fJ per bit of information transferred. We explored combinations of two-dimensional materials with thicknesses below 1 nm that exhibited data transfer times of 3 ps under laboratory conditions. If these conditions could be met in real devices, data transfer at several 100s GHz seems feasible with such optical transceivers.
We have tested a variety of different nanomaterials and explored their potential towards application in fast optical transceivers. This includes PbS, CuS and CdSe nanocrystals as well as Au nanoclusters. Most notably, we found that the surfaces of CdSe (https://arxiv.org/abs/1904.04752(öffnet in neuem Fenster)) and CuS nanocrystals (https://arxiv.org/abs/1903.05037(öffnet in neuem Fenster)) can be decorated with organic dyes to greatly expand their sensitivity for optical wavelengths which are typically not detected by these materials. In contrast, three-dimensional supercrystals of Au nanoclusters were found to exhibit highly interesting electric transport properties owing to the exceptionally large degree of long-range structural order (https://doi.org/10.1038/s41467-020-19461-x(öffnet in neuem Fenster)) but they turned out to be chemically too unstable under intense light pulses. However, this discovery has enabled a follow-up study which utilizes this material for the cost-effective fabrication of electrical micro-circuits (https://doi.org/10.1002/smtd.202201221(öffnet in neuem Fenster)). We have also explored the potential of Au nanorods for photodetection (https://doi.org/10.3390/nano13091466(öffnet in neuem Fenster)). Following a similar idea, we have established a new method to print thin stripes of nanocrystal films onto electrical micro-circuits for further use as optical transceivers (https://arxiv.org/abs/2006.11202(öffnet in neuem Fenster)). To complement the findings on optical transceivers based on nanocrystal/organic dye hybrid materials, we have detailed the interaction between these two material classes in experiment (https://arxiv.org/abs/2005.00898(öffnet in neuem Fenster)) as well as with an extensive review of the field (https://doi.org/10.1002/anie.201916402(öffnet in neuem Fenster)). We have designed optical transceivers based on CdSe nanocrystals and organic dyes with a 3dB bandwidth of 85 KHz (http://arxiv.org/abs/2109.02049(öffnet in neuem Fenster)). We established that the maximum speed possible with state-of-the-art PbS nanocrystals is likely to be limited around 1 ns (https://doi.org/10.48550/arXiv.2112.11987(öffnet in neuem Fenster)) highlighted pitfalls in accurately determining their speed (https://doi.org/10.48550/arXiv.2209.03676(öffnet in neuem Fenster)) and we concluded our exploration of such nanocrystals coupled to organic dyes with a review of the field (https://doi.org/10.48550/arXiv.2202.06050(öffnet in neuem Fenster)). We changed our focus material class to two-dimensional transition metal dichalocogenides and achieved a continuous development of the electrical bandwidth with such transceivers from 2.6 MHz for WSe2 (https://doi.org/10.48550/arXiv.2203.14053(öffnet in neuem Fenster)) over 18 MHz for MoS2 (https://doi.org/10.1039/d3na00223c(öffnet in neuem Fenster)) to >230 MHz for WSe2 (https://doi.org/10.1039/d4lf00019f(öffnet in neuem Fenster)). We studied the electronic structure of MoS2 nanomaterials by spectroelectrochemistry (https://doi.org/10.1002/smll.202207101(öffnet in neuem Fenster)) and monitored the effect of adsorbing organic dyes to their surface in this respect (https://doi.org/10.26434/chemrxiv-2024-4kc0h(öffnet in neuem Fenster)) also with a special emphasis on the orientation of the molecules (https://doi.org/10.26434/chemrxiv-2023-tj7m0(öffnet in neuem Fenster)). Combining transition metal dichalocogenides with black phosphorus enabled us to realize response times of 26 ps (https://doi.org/10.1038/s41467-024-49760-6(öffnet in neuem Fenster)) which we recently even surpassed with a 3 ps response for combining WS2 with graphene (https://doi.org/10.26434/chemrxiv-2024-d352b(öffnet in neuem Fenster)).
The COINFLIP project has made significant advances in fast optical transceivers through the exploration of various nanomaterials. Notably, CdSe and CuS nanocrystals, when combined with organic dyes, demonstrated expanded optical sensitivity, while Au nanoclusters revealed remarkable electric transport properties, leading to new avenues for micro-circuit fabrication. A key breakthrough was the achievement of ultra-fast response times—3 ps with WS2/graphene structures, surpassing state-of-the-art capabilities.
The project also developed new, scalable methods for integrating nanomaterials into devices, notably printing nanocrystal films onto micro-circuits for optical transceivers. These innovations offer immense potential for faster, energy-efficient communication networks, meeting the growing demand for high-speed data transmission. With nanomaterials like transition metal dichalcogenides, the project progressed from 2.6 MHz to 230 MHz in optical transceiver speed, paving the way for further technological advancements.
In addition, the project addressed fundamental limitations of materials like PbS nanocrystals, capping their speed at 1 nanosecond, and provided critical insights into combining nanocrystals and dyes. A significant societal impact of this research is the potential for optical interconnects with femtojoule power consumption, providing an energy-efficient solution to the limitations of modern electronics, which are nearing maximum power density. The project's innovations could revolutionize data centers and telecommunications systems, enabling faster, more efficient optical communication technologies.
In the future, we expect to refine material combinations further and improve response times, setting new standards for speed and efficiency in optical transceivers. These advancements promise long-term societal benefits by reducing energy consumption and enabling faster, more reliable global communication infrastructure.
The project also developed new, scalable methods for integrating nanomaterials into devices, notably printing nanocrystal films onto micro-circuits for optical transceivers. These innovations offer immense potential for faster, energy-efficient communication networks, meeting the growing demand for high-speed data transmission. With nanomaterials like transition metal dichalcogenides, the project progressed from 2.6 MHz to 230 MHz in optical transceiver speed, paving the way for further technological advancements.
In addition, the project addressed fundamental limitations of materials like PbS nanocrystals, capping their speed at 1 nanosecond, and provided critical insights into combining nanocrystals and dyes. A significant societal impact of this research is the potential for optical interconnects with femtojoule power consumption, providing an energy-efficient solution to the limitations of modern electronics, which are nearing maximum power density. The project's innovations could revolutionize data centers and telecommunications systems, enabling faster, more efficient optical communication technologies.
In the future, we expect to refine material combinations further and improve response times, setting new standards for speed and efficiency in optical transceivers. These advancements promise long-term societal benefits by reducing energy consumption and enabling faster, more reliable global communication infrastructure.