Erbium atoms in silicon: A prime candidate for quantum networks

https://phys.org/news/2022-11-erbium-atoms-silicon-prime-candidate.html

"endowed with nanometer-fine structures... light-conducting elements... irradiated silicon with erbium ions... comparatively moderate temperature... stable integration individual erbium atoms in crystal... narrow spectral lines in emission of infrared light 10 kilohertz...favorable for quantum network... excellent optical properties at 8 Kelvin (degrees above absolute zero). Such a temperature can be achieved by cooling in a cryostat with liquid helium"