The realization of a scalable architecture for quantum information processing is a major challenge for quantum science. A promising approach is based on emitters in nanostructures that are coupled by light. Here, we show that erbium dopants can be reproducibly integrated at well-defined lattice sites by implantation into pure silicon. We thus achieve a narrow inhomogeneous broadening, less than 1 GHz, strong optical transitions, and an outstanding optical coherence even at temperatures of 8 K, with an upper bound to the homogeneous linewidth of around 10 kHz. Our study thus introduces a promising materials platform for the implementation of on-chip quantum memories, microwave-to-optical conversion, and distributed quantum information processing.
@article{arxiv.2108.05120,
title = {Narrow optical transitions in erbium-implanted silicon waveguides},
author = {Andreas Gritsch and Lorenz Weiss and Johannes Früh and Stephan Rinner and Andreas Reiserer},
journal= {arXiv preprint arXiv:2108.05120},
year = {2022}
}