Heidelberg 2015 – wissenschaftliches Programm
Q 15.65: Poster
Montag, 23. März 2015, 17:00–19:00, C/Foyer
Towards a cryo-lattice clock at PTB — •Ali Al-Masoudi, Sören Dörscher, Stephan Falke, Sebastian Häfner, Stefan Vogt, Uwe Sterr, and Christian Lisdat — Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig
Optical clocks have become valuable tools for frequency metrology with applications ranging from the search for physics beyond the standard model to relativistic geodesy. Strontium lattice clocks offer high stabilities, but their best uncertainty budgets have been dominated by the Stark shift due to black-body radiation. With the atomic sensitivity itself well known from our previous measurements, knowledge and control of the thermal environment have been the limiting factor. Several groups have recently demonstrated approaches to overcome this limitation and reached relative uncertainties as low as 5 × 10−18. We report on the integration of a thermally well-controlled, cryogenic environment into our existing setup. We expect to achieve a total relative uncertainty of 1 × 10−17, limited by constraints of our optical lattice geometry. Finally, we present the recent progress of a new physics package for a next-generation 87Sr clock aiming at uncertainties of 1 × 10−18 and better. It is designed to allow detailed investigations of further points of concern, e.g. higher-order contributions to the lattice light shifts. This work is supported by QUEST, the DFG within CRC 1128 (geo-Q) and RTG 1729, and the EMRP within IND14, ITOC, and QESOCAS. The EMRP is jointly funded by the EMRP-participating countries within EURAMET and the European Union.