Precisely positioned Quantum Dots enable scalable and reproducible Integration of Quantum Light Sources on Semiconductor Chips –
Photonic Quantum Chips are considered a key technology for future communication and computing applications. One of the major challenges in their fabrication has been that the required Quantum Light Sources – so-called Semiconductor Quantum Dots – form at random locations on the chip during crystal growth. As a result, suitable Quantum Dots first had to be identified before photonic structures could be fabricated around them. This process has significantly hindered scalable and reproducible manufacturing. Researchers from the QR.N consortium at the Berlin and Oldenburg sites have now developed a solution to this challenge. Using a novel Quantum Chip Architecture, Quantum Dots are formed precisely at the positions where they are required in the final device. This is achieved through carefully engineered stressors embedded in the substrate, which generate localized strain fields that precisely control the growth of the Quantum Dots. The approach lays an important foundation for the scalable and industry-compatible fabrication of photonic Quantum Chips. The results were published in early June 2026 in the journal Light: Science & Applications.
In the reported approach, the position of the Quantum Dots is defined already during crystal growth. The Quantum Dots are then integrated directly into nanophotonic resonators, which efficiently couple the emitted light and make it available for Quantum Technology Applications. Using this method, the researchers achieved an exceptional level of reproducibility that has rarely been demonstrated in Semiconductor Quantum Photonics. In addition, they combined imaging, spectroscopic, and quantum-optical measurement techniques with numerical simulations to investigate how even the smallest deviations in Quantum Dot Positioning affect device performance. Their findings provide important design guidelines for the development of future Quantum Chips.
By ensuring that Quantum Dots form exactly where they are needed within the photonic device, the new approach paves the way from individually optimized laboratory demonstrators to scalable, reproducible, and industrially viable manufacturing of photonic Quantum Chips. As a result, volume manufacturing of photonic Quantum Systems has moved a decisive step closer. Click here for the paper.
Source reference: https://www.tu.berlin/news/pressemitteilung/tu-berlin-ebnet-weg-zur-serienfertigung-von-quantenchips
