Is the time right for a redefinition of the second by optical atomic clocks?

8th Symposium on Frequency Standards and Metrology 2015

Gill, Patrick^1

National Physical Laboratory (NPL), Teddington, Middlesex

TW11 0LW, United Kingdom^1

关键词: Current performance;    Optical atomic clocks;    Optical clocks;    Redefinition of the seconds;    Time-scales;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/723/1/012053/pdf
DOI  :  10.1088/1742-6596/723/1/012053

来源: IOP

【 摘 要 】

Given the dramatic rate of progress in optical atomic clocks over the last decade, this paper presents the current state of play, and considers the possibilities, implications and timescales for a potential redefinition of the SI second in terms of an optical reference transition. In particular, the question of choice of a future standard is addressed, together with the requirements to accurately compare realisations of such standards, both for clocks local to, and remote from each other. Current performances of various optical clock systems are examined and possibilities for moving beyond potential limitations by alternative strategies are outlined.