An ${}^{27}$Al${}^{+}$ quantum-logic clock with systematic uncertainty below $10^{-18}$

S. M. Brewer, J. -S. Chen, A. M. Hankin +5

We describe an optical atomic clock based on quantum-logic spectroscopy of the ${}^1$S${}_0$ $\leftrightarrow$ ${}^3$P${}_0$ transition in ${}^{27}$Al${}^{+}$ with a systematic uncertainty of…