We report the detection of individual emitters in silicon belonging to seven different families of optically active point defects. These fluorescent centers are created by carbon implantation of a commercial siliconon-insulator wafer usually employed for integrated photonics. Single photon emission is demonstrated over the 1.1-1.55 μm range, spanning the O and C telecom bands. We analyze their photoluminescence spectra, dipolar emissions, and optical relaxation dynamics at 10 K. For a specific family, we show a constant emission intensity at saturation from 10 K to temperatures well above the 77 K liquid nitrogen temperature. Given the advanced control over nanofabrication and integration in silicon, these individual artificial atoms are promising systems to investigate for Si-based quantum technologies.

Controlling the quantum properties of individual fluorescent defects in silicon is a key challenge toward large-scale advanced quantum photonic devices. Research efforts have so far focused on extrinsic defects based on impurities incorporated inside the silicon lattice. Here, we demonstrate the detection of single intrinsic defects in silicon, which are linked to a tri-interstitial complex called the W-center, with a zero-phonon line at 1.218 μm. Investigating their single-photon emission properties reveals new information about this common radiation damage center, such as its dipolar orientation and its photophysics. We also identify its microscopic structure and show that, although this defect does not feature electronic states in the bandgap, Coulomb interactions lead to excitonic radiative recombination below the silicon bandgap. These results could set the stage for numerous quantum perspectives based on intrinsic luminescent defects in silicon, such as integrated quantum photonics and quantum communications.