Photoactivation of Color Centers Induced by CW Laser Irradiation in Ion-Implanted Diamond.

Split-vacancy color centers in diamonds are promising solid-state platforms for the implementation of photonic quantum technologies. These luminescent defects are commonly fabricated upon low-energy ion implantation and subsequent thermal annealing. Their technological uptake will require the availability of reliable methods for the controlled, large-scale production of localized individual photon emitters. This task is partially achieved by controlled ion implantation to introduce selected impurities in the host material and requires the development of challenging beam focusing or collimation procedures coupled with single-ion detection techniques. We report on the protocol for the direct optical activation of split-vacancy color centers in diamond via localized processing with a continuous-wave laser at mW optical powers. We demonstrate the activation of photoluminescent Mg- and Sn-related centers at both the ensemble and single-photon emitter levels in ion-implanted, high-purity diamond crystals without further thermal processing. The proposed lithographic method enables the activation of individual color centers at specific positions of a large-area sample by means of a relatively inexpensive equipment offering real-time, in situ monitoring of the process.