27 Nov. Scalable future photonics quantum hardware
The development of scalable quantum information technologies is one of the central goals of current quantum physics research. Researchers at the University of Copenhagen, the University of Basel, and Ruhr University Bochum are pursuing a new approach to photonic quantum hardware. According to those involved, the joint work will be funded by the European Research Council with €11.5 million over the next six years as part of the ERC Synergy Grant ‘Phoqus’.
Quantum dots as a source of entangled photons
The aim of the international project is to use quantum dots to generate entangled photons – i.e., photons that are intertwined in terms of quantum mechanics – on demand. These will be photon sources implemented on a solid-state platform. By controlling the quantum dots with laser fields and collecting the emitted photons with optical nanostructures, it should be possible to generate entangled states of photons on demand. “These states are the essential resource for photonic quantum information processing,” explains Arne Ludwig, who is involved in Phoqus from Bochum. According to the researchers, a particular advantage of the chosen approach is that it is highly modular and therefore scalable: once sources of sufficiently high quality have been realized, the technology can be scaled up to larger processors by building additional sources.
Development steps: From entangled photons to quantum processors
As part of the project, quantum dots and photonic nanostructures are being developed. According to the researchers, the quantum dots are to be designed in such a way that they emit multi-photon entangled initial states of up to ten photons when required. Quantum information processors can then be built that process some of these fundamental initial states and thus entangle them into even more complex initial states. Finally, proof-of-principle experiments will show how the technology can be scaled up to fully functional quantum information processors. The project will thus lay the foundation for future photonic quantum technologies.
Two quantum dots forming a lattice of entangled photons. Image: University of Basel, Department of Physics
“This funding is a dream come true,” says Ludwig. “Ideas that previously only existed on paper can now be turned into reality with a strong team and technological capabilities. Among other things, the project enables us in Bochum to reliably provide samples for quantum optics groups as a partner.”
Source: www.ruhr-uni-bochum.de
Image: RUB, Kramer