Nanophotonic lithium niobate memory devices that can store telecommunication-wavelength quantum light states for over a microsecond
https://www.eurekalert.org/news-releases/1147082 "optical quantum memory temporarily holds photon's quantum state so signals arriving from different network nodes can be synchronized, but photons often arrive degraded... overcome integrating rare-earth ions into low optical loss nanoscale waveguides fabricated out of thin-film lithium niobate, creating microchip-compatible platform that successfully halts/ retrieves fragile quantum states without converting them into electrical signals... long-distance quantum networks, scalable quantum internet"