TY - JOUR AU - Samuel Brewer AU - Jwo-Sy Chen AU - Aaron Hankin AU - Ethan Clements AU - Chin-Wen Chou AU - David Wineland AU - David Hume AU - David Leibrandt C2 - Physical Review Letters DA - 2019-07-15 04:07:00 LA - en PB - Physical Review Letters PY - 2019 TI - An 27Al+ quantum-logic clock with systematic uncertainty below 10-18 UR - https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=927399 ER -