A transportable strontium optical lattice clock towards space

[摘要] This work presents the realisation and characterisation of the world’s smallest transportable optical lattice clock as part of the Space Optical Clocks 2 EU project built at the University of Birmingham. Housed in a transportable rack of dimensions 170 x 100 x 60 cm, such a device aims to measure the frequency of the doubly-forbidden 1S0−3P0 clock transition in 88Sr in an unprecedented compact apparatus as a major technological milestone towards an optical clock upon the International Space Station. A master optical clock in space would serve with unrivalled accuracy and stability to disseminate a precise and accurate reference for terrestrial clocks and the coordination of international time. Such a clock has the potential to redefine the second, revolutionise timekeeping and precision measurements, and perform fundamental science experiments in space. Using a combination of novel design, innovative cooling techniques, and robust, compact commercially available products, the clock portability, robustness and operational simplicity have been improved. The apparatus simply and effectively cools and traps up to 105 88Sr atoms at a temperature of 1.3±0.2μK in an optical lattice with a lifetime of 0.52±0.01s within 400ms. The most recent preliminary clock spectroscopy measurement was 3.6 ± 0.2Hz. The instability of the clock has been measured at 8×10−17 after averaging for 300s with the goal instability being 5.8×10−17 within the same averaging time. These results show the experiment will lead transportable optical clock research and continue with the goal of being a master clock in space.

[发布机构] University:University of Birmingham;Department:School of Physics and Astronomy

[关键词] Q Science;QC Physics