Spatial Distribution Control of Room‐Temperature Single Photon Emitters in the Telecom Range from GaN Thin Films Grown on Patterned Sapphire Substrates

Spatial distribution‐controlled single‐photon emitters operating is demonstrated in telecom wavelength range at room‐temperature with GaN thin film grown on a patterned sapphire substrate (PSSs) with varying pattern sizes and dimensions. The analysis focuses on the various optical properties of defects within the GaN thin film, particularly their interactions with PSS. The confocal fluorescence mapping at room temperature revealed localized single‐photon emitters inside the GaN layers located between the patterns. In addition, compared to conventional sapphire substrates, PSS can scatter photons outside the total reflection cone, thereby enhancing the light extraction efficiency. From the samples, the single photon emission is observed in the telecom wavelength ranging from 1.1 to 1.35 µm at room temperature, which is critical for advancing quantum communication technologies, and elucidate how the physical characteristics of PSS influence the performance and efficiency of GaN‐based single‐photon emitters.