International Exchange Award – Cuprous oxide: an emerging platform to study Rydberg solid-state dynamics

Christoforos loading samples in one of the furnaces

Christoforos Iakovou, a PhD student at the University of Cambridge was awarded an M4QN international exchange award to visit Prof. Matthew Zervos at the Nanostructured Materials and Devices Laboratory, University of Cyprus. The visit took place from 15-30 March 2026.

Cuprous oxide: an emerging platform to study Rydberg solid-state dynamics

The primary aim of Christoforos’s visit was to gain hands-on experience in highly controlled thermal oxidation workflows for producing synthetic cuprous oxide of sufficient quality to support highly excited Rydberg exciton states, and to translate that know-how into tangible progress for an ongoing Cambridge–Cyprus collaboration.

During the visit Christoforos worked closely with the host team to refine oxidation procedures, with particular emphasis on process control and contamination minimisation. In parallel, he benchmarked existing collaborative samples and used that feedback to design and fabricate a new series of specimens. These were produced through systematic variation of high-leverage processing parameters, enabling them to map the practical limits of their current approach, identify dominant constraints, and define clearer routes for improvement.

Benefits to the UK materials and quantum community

This exchange strengthens the UK quantum materials ecosystem by reinforcing the connection between materials processing and quantum-optical performance. In solid-state quantum platforms, progress is often constrained not by conceptual limitations but by the ability to reproducibly control defect density, contamination, and structural disorder, challenges that are frequently exacerbated by fragmented process knowledge and inconsistent workflows. By transferring practical expertise in controlled oxidation and contamination-aware processing, the visit enhances the capability to develop device-relevant materials through systematic, repeatable workflows rather than reliance on isolated high-performing specimens.

The collaboration complements existing UK strengths in quantum measurement and characterisation by embedding deeper process-level understanding within that framework, enabling more efficient iteration between growth and evaluation. Although centred on cuprous oxide, the insights gained are directly applicable to other impurity-sensitive quantum materials where charged defects and surface/interface disorder govern coherence and optical performance.

The visit aligns closely with M4QN’s objectives by fostering international collaboration, strengthening interdisciplinary links between materials science and quantum technologies, and supporting the development of researchers who operate across both domains, with research objectives aligned to national quantum priorities.

Visit Outcomes

The visit produced a new set of synthetic cuprous oxide specimens through systematic variation of key processing parameters, enabling both groups to map the operational limits of the current approach and identify clearer optimisation pathways. Structural characterisation of these samples is now underway in Cambridge, informing a refined understanding of the achievable processing window.

Both groups agreed on a focused next iteration cycle, specifying parameters to explore and measurements to validate progress, with the aim of accelerating optimisation and improving reproducibility. The combined results are forming the basis of planned high-impact publications, and discussions during the exchange identified new research directions that neither group had previously pursued independently.

This collaboration marks an important step toward steering the field of Rydberg excitons in cuprous oxide away from reliance on rare “hero” natural specimens and toward reproducible, device-compatible workflows capable of supporting controlled studies of Rydberg-mediated quantum optical phenomena in solids.