Illinois Quantum Memory Chip Stores 20 Photons Past Microsecond on Commercial Telecom Platform

Steve A Johnson/pexels.com Researchers at the University of Illinois Urbana-Champaign have demonstrated an on-chip quantum memory that simultaneously cleared two of the hardest requirements standing between quantum networking research and manufacturable hardware: it stored multiple photons at the same time, and it did so for longer than a microsecond — all on a chip platform that commercial photonics foundries already know how to build at wafer scale. The paper, published in Nano Letters, arrived just days after IonQ announced a world-first quantum interconnect breakthrough that proved the field urgently needs exactly this type of component, according to IonQ's press release. The paper, led by physics professor Elizabeth Goldschmidt at UIUC's Grainger College of Engineering, describes an integrated nanophotonic chip built from erbium-doped thin-film lithium niobate (TFLN) — a material already used in wafer-scale classical photonics manufacturing for fiber-optic telecommunications. The device stored up to 20 separate photons simultaneously, achieved storage times as long as 1.2 microseconds, and preserved the quantum character of the stored light with a measured fidelity lower bound of 96.6%. "Its promise is in its simplicity: we've taken something that can typically only be done in a highly…