1304.5944 (Johannes Borregaard et al.)

Efficient atomic clocks operated with several atomic ensembles    [PDF]

Johannes Borregaard, Anders S. Sørensen

Atomic clocks are typically operated by locking a local oscillator (LO) to a single atomic ensemble. In this article we demonstrate a scheme where the LO is locked to several atomic ensembles instead of one. This results in an exponential improvement compared to the conventional method and provides a stability of the clock scaling as $(\alpha N)^{-m/2}$ with $N$ being the number of atoms in each of the $m$ ensembles and $\alpha$ is a constant depending on the protocol being used to lock the LO. We find an improvement for $N\geq20$ for clocks operated with the conventional Ramsey protocol and $N\geq7$ for clocks operated with a more efficient, adaptive measurement strategy.

View original: http://arxiv.org/abs/1304.5944