Ion-induced telecom single-photon emitters in silicon

Single-photon emitters (SPEs) are one of the elementary building blocks for photonic quantum information and optical quantum computing. One of the upcoming challenges is the monolithic photonic integration and coupling of single-photon emission, reconfigurable photonic elements, and single-photon detection on a sili- con chip in a controllable manner. Particularly, fully integrated SPEs on-demand are required for enabling a smart integration of advanced functionalities in on-chip quantum photonic circuits. The major challenge in realizing a fully monolithic, photonic integrated circuitry lies in the development of a quantum light source in silicon since the indirect nature of the small energy bandgap does not allow for efficient PL emission. Nev- ertheless, below-bandgap light emission can be used for good advantage by exploiting extrinsic and intrinsic point defects acting as SPEs. Indeed, the isolation of SPEs, such as G-, W-, and T-centers, in the optical telecom- munication O-band has been recently realized in silicon [1-4]. In all these cases, however, SPEs were created uncontrollably in random locations, preventing their scalability.
We present mask-free nanofabrication involving a quasi-deterministic creation of single G- and W-centers in silicon wafers using focused-ion beam (FIB) writing. We also implement a scalable, broad-beam implan- tation protocol compatible with the complementary-metal-oxide-semiconductor (CMOS) technology to fabri- cate telecom SPEs at desired positions on the nanoscale [5].
[1] M. Hollenbach et al., Optics Express 28, 26111 (2020) [2] W. Redjem et al., Nature Electronics 3, 738 (2020)
[3] Y. Baron et al., ACS Photonics 9, 2337 (2022)
[4] D. B. Higginbottom et al., Nature 607, 266 (2022)
[5] M. Hollenbach et al., Nat. Commun. 13, 7683 (2022)