Detection of Single W-Centers in Silicon

Abstract

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.

Time-Resolved Photoionization Detection of a Single Er3+ Ion in Silicon

“…For example, the negatively charged nitrogen-vacancy (NV – ) centers in diamond enabled long-distance quantum entanglement and various innovative biomedical applications , via optically detected magnetic resonance (ODMR), thanks to the spin-dependent fluorescence and long coherence time at both cryogenic and room temperatures. Other single optical centers with relatively intense fluorescence include radiation damage centers in silicon, − antisite defects and divacancy defects in SiC, and defects in GaN . The exceptional performance of these optical centers depends on efficient photon collection via confocal microscopy and/or solid immersion lenses, , which impose constraints on the scale-up of these single optical centers.…”

Effect of Localization on Photoluminescence and Zero-Field Splitting of Silicon Color Centers

“…A third defect structure, dubbed I 3 -V, with a formation energy lying between that of the previous two candidates [10,11], was discovered using molecular dynamics simulations [9]. While this configuration had the appropriate symmetry and exhibited a LVM with the correct energy [10,11], the electronic structure of its defect levels [10,11,24] is still hotly debated, and it has been proposed that the optical transition stems from the recombination of an exciton localized at the defect by Coulomb interactions, even in the absence of defect levels in the band gap [24].…”

“…Excited state calculations for each defect are preformed by manually constraining the orbital occupations to excite one electron into an unoccupied band. Such an approach has been successfully used in combination with hybrid functionals to study the excited state properties of the nitrogen-vacancy (NV) defect in diamond [37], as well as various silicon defects [4,12,24].…”

Light Emitting Si‐Based Mie Resonators: Toward a Huygens Source of Quantum Emitters

“…[ 25 ] At low temperature (≈10 K), their photoluminescence is composed of a sharp zero‐phonon line (ZPL) and a low‐energy phonon‐side band covering a broad wavelength range. [ 26–34 ] Some of these impurities feature a large quantum efficiency (e.g., of the order of unity [ 28 ] ), relatively fast recombination lifetime (less than 10 ns [ 24 ] ), large Debye–Waller factor (larger than 30% [ 29 ] ) and a spin degree of freedom, offering a spin‐photon interface. [ 27,31,34 ] In spite of their relevance in quantum optics, the integration of these emitters in photonic devices has been, so far, mostly limited to photonic crystals and photonic metasurfaces, requiring complex fabrication steps (e.g., e‐beam lithography and reactive ion etching).…”