Breakthrough: quantum defects in diamond

During June 2025, a team of authors from the universities of Oxford, Cambridge and Manchester published their ground-breaking paper 'Laser activation of single group-IV colour centres in diamond' in Nature Communications.

In this paper, they demonstrate how they addressed the challenge of realising the required (and precise) single defect positioning and activation for scalable device fabrication in spin-photon interfaces, for use in quantum networks.

In essence, the authors created a two-step fabrication method for tin vacancy centres.  The resulting ion implementation performed with sub-50nm resolution, and a dosage which could be controlled precisely.

As co-author Professor Jason Smith says:

"This breakthrough gives us unprecedented control over single tin-vacancy colour centres in diamond - a crucial milestone for scalable quantum devices.  What excites me most is that we can watch, in real time, how the quantum defects are formed".

This breakthrough signals the way towards achieving greater understanding of defect structures and dynamics during the annealing process in implanted colour centres in diamond, and wide-bandgap materials.

For a longer read of this exciting news, visit 'New Breakthrough enables precise activation of quantum features in diamond' on the University of Oxford's website.