TUM explores erbium dopants in nanophotonic silicon resonators as a scalable hardware platform for quantum networks. Compared with established approaches, erbium emitters operate directly at telecom wavelengths, avoiding the complexity, noise, and loss of frequency conversion. The devices are fully compatible with standard silicon foundry processes, enabling large-scale fabrication. Coherent operation is possible up to 8 K, allowing the use of compact, low-cost cryogenic systems with high cooling power. Control can be implemented using a simple fiber-based telecom setup with a single laser and electro-optic IQ modulators. In addition, nuclear spins of ^167Er provide quantum memories with coherence times of several seconds, sufficient for long-distance quantum repeater links.

Within QIA, TUM aims to demonstrate that this silicon-compatible approach can enable compact, cost-effective, and high-performance quantum networking nodes suitable for scalable quantum internet architectures.

Members from TUM