Scalable and telecom single-erbium system with record-long room-temperature quantum coherence
Researchers created a CMOS-compatible quantum system using single erbium ions embedded in sub-5 nm silicon-based hollow nanopillars. This novel nanoscale engineering achieves deterministic spatial isolation of individual ions, suppressing noise and interactions. The system demonstrates record room-temperature optical coherence times exceeding 500 microseconds in the telecom C-band, paving the way for scalable quantum technologies.