Dresden 2026 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

QI: Fachverband Quanteninformation

QI 6: Implementations II

QI 6.1: Invited Talk

Tuesday, March 10, 2026, 09:30–10:00, BEY/0245

Erbium dopants for quantum networks — •Andreas Reiserer — Technical University of Munich, TUM Center for Quantum Engineering (ZQE), Am Coulombwall 3A, 85748 Garching, Germany

Despite decade-long research into different physical systems, demonstrating a scalable platform for quantum networks and distributed quantum information processing remains an outstanding challenge. In this context, our group investigates the use of erbium dopants in silicon and silicate crystals. This platform offers unique potential for up-scaling: First, erbium dopants can exhibit second-long coherence in a temperature range accessible with 4He cryocoolers. Second, the optical transition of erbium is among the narrowest spectral features ever measured in a solid. Thus, frequency-multiplexed addressing of individual dopants gives access to an unprecedented qubit density. Finally, by embedding the dopants into slow-light waveguides or optical resonators with a high quality factor, the optical lifetime can be reduced via the Purcell effect. This has enabled lifetime-limited photon emission in the telecommunications C-band, where optical fiber losses are minimal. Furthermore, it has paved the way for the optical spin readout of erbium dopants and for spectroscopy of their surrounding nuclei. Taken together, our results thus establish erbium dopants as a promising new hardware platform that may facilitate the implementation of scalable quantum networks and repeaters based on single emitters at telecommunications wavelengths.

Keywords: Quantum repeaters; Rare-earth dopants; Erbium; Distributed quantum information processing