Optically accessible donor qubits in ZnO

Donors in semiconductors have been studied as a qubit platform for over 20 years. Here we present our work on synthesizing and isolating single donors in zinc oxide (ZnO). The direct band gap nature of ZnO enables efficient access to the donor electron via the donor-bound exciton. Here we demonstrate synthesis of indium (In) donors via ion implantation and annealing with properties on par with In donors incorporated in situ during growth including: a narrow inhomogeneous linewidths (< 10 GHz), spin initialization, and long longitudinal spin relaxation (> 100 ms). Next we demonstrate single In donor isolation for in situ doped In via plasma-enhanced focused ion beam milling. An outlook and progress toward single implanted In isolation and access to the In nuclear spin will also be presented.