Speaker
Description
Optical atomic frequency standards and clocks are continuing to push the boundaries of precision measurement with fractional frequency uncertainties from systematic offsets now below 1x10$^{-18}$ [1]. With this high level of performance comes the ability to not only carry out precision frequency metrology [2] but also to investigate fundamental physics such as local Lorentz invariance [3] and to perform searches for dark matter [4,5]. Additionally, the anticipated redefinition of the SI second, which is expected to be based on an optical frequency, makes this a particularly exciting time for frequency metrologists.
At the National Physical Laboratory (NPL) in the UK we have constructed an optical frequency standard based on a single $^{171}$Yb$^+$ ion tightly confined in space by an end-cap style Paul trap [6]. We will describe our current generation trap and experimental apparatus focussing on the trap design, which we determine to contribute only a 0.5x10$^{-18}$ fractional uncertainty to the clock uncertainty budget. We will also present our new generation of ion trap currently under construction. Based largely on the previous design but with some significant upgrades, this trap provides a highly controllable environment, as well as excellent optical access for probing the ion.
References:
[1] Brewer et al., PRL 123, 033201, (2019).
[2] Baynham et al., J. Mod. Opt., 65:5-6, 585-591, (2017)
[3] Sanner et al., Nature 567, 204 (2019)
[4] Roberts et al., arXiv, 1907.02661v2, (2019).
[5] Wcisło et al., Science Adv. 4, 12, (2018)
[6] Nisbet-Jones et al., App. Phys. B, 122:57, (2016)
