Optical control of quantum dots can enable future quantum technologies

Quantum dots (QDs) generate single photons or entangled photons pairs that can be used for encryption and precise measurements, placing them at the core of technologies like quantum communication, sensing, and computing. Their rapid progress will soon lead to their commercialization for future integration onto chip-scale devices.

Uniting diverse experimental techniques into a single reference, Vikas Remesh and Gregor Weihs prepared a comprehensive guide for optically controlling QDs.

“Optical control of QDs now spans multiple domains, including materials science, nanofabrication, ultrafast optics, and quantum photonics,” Remesh said. “While significant advances have been made in each of these areas, the knowledge is often fragmented across different communities.”

Transforming QDs into functional circuit components requires pure, bright, and indistinguishable photon states. The main challenge to accomplishing this is achieving full control over all the optical degrees of freedom, including frequency and polarization.

“The last few years have seen steady progress in these areas, yet there is still room for improvement to reach the demands set by device architectures,” Remesh said.

To eventually integrate QDs into nanophotonic platforms, there are still many challenges that need to be addressed, including the scalability of methods for growing QDs and tuning their characteristics. However, Remesh says that with the help of ultrafast optics, nanophotonics, and machine learning techniques, the field is rapidly closing in on achieving full control of QD photon properties.

“It is very interesting to see how ideas from different fields are merging to make these developments happen,” he said. “It is a testament to the fact that only cross-disciplinary synergy can help solve some of longstanding limitations in QD-based systems.”

Source: “Experimental techniques in optical quantum dot control,” by Vikas Remesh and Gregor Weihs, Applied Physics Reviews (2026). The article can be accessed at https://doi.org/10.1063/5.0308236 .

This paper is part of the Quantum Light Collection, learn more here .