Fabrication of quantum emitters in aluminium nitride by Al-ion implantation and thermal annealing

• Published in: arXiv.org 2023-10
• Main Authors: E Nieto Hernández, Yağcı, H B, Pugliese, V, Aprà, P, Cannon, J K, Bishop, S G, Hadden, J, Tchernij, S Ditalia, Olivero, Bennett, A J, neris, J
• Format: Article
• Language: English
• Subjects: Aluminum nitride; Annealing; Cleanrooms; Color centers; Defects; Density; Diamonds; Emission analysis; Emitters; Energy gap; Energy levels; Fluence; Gallium nitrides; Ion implantation; Photons; Room temperature
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2310.20540

Single-photon emitters (SPEs) within wide-bandgap materials represent an appealing platform for the development of single-photon sources operating at room temperatures. Group III- nitrides have previously been shown to host efficient SPEs which are attributed to deep energy levels within the large bandgap of the material, in a way that is similar to extensively investigated colour centres in diamond. Anti-bunched emission from defect centres within gallium nitride (GaN) and aluminium nitride (AlN) have been recently demonstrated. While such emitters are particularly interesting due to the compatibility of III-nitrides with cleanroom processes, the nature of such defects and the optimal conditions for forming them are not fully understood. Here, we investigate Al implantation on a commercial AlN epilayer through subsequent steps of thermal annealing and confocal microscopy measurements. We observe a fluence-dependent increase in the density of the emitters, resulting in creation of ensembles at the maximum implantation fluence. Annealing at 600 {\deg}C results in the optimal yield in SPEs formation at the maximum fluence, while a significant reduction in SPE density is observed at lower fluences. These findings suggest that the mechanism of vacancy formation plays a key role in the creation of the emitters, and open new perspectives in the defect engineering of SPEs in solid state.