Misc,
Near-Unitary Spin Squeezing in 171Yb
(2019)cite arxiv:1901.10499Comment: 5 pages, 4 figures.
Abstract
We report nearly unitary spin squeezing between the magnetic sublevels of the
ground state of $^171$Yb, an atom with an optical clock transition. The
collective spin of $\sim10^3$ atoms inside a cavity is squeezed using light
detuned from the system's resonances. We demonstrate an interferometer
operating with a squeezed state of nearly Heisenberg-uncertainty-limited area
that improves the averaging time over the standard quantum limit (SQL) by a
factor of 3.7(2). The observed metrological gain is limited by the state
readout to 9.4(4) dB, while the generated states offer a spin noise suppression
of 15.8(3) dB and a metrological gain of 12.9(1) dB over the SQL. In the
future, the demonstrated squeezing between nuclear spin states can be directly
mapped onto an electronic optical-clock transition to improve the performance
of an $^171$Yb optical clock.
