Impact

Outcomes for industrial and other user communities

Optical lattice clocks are starting to gain industrial uptake, after two decades of academic development, and the maturity of the laser technologies required to operate them. This uptake is motivated by emerging field applications such as geodesy or optical time scales, and by the dominant position of optical lattice clocks for the next definition of the second. In Japan, compact transportable Sr clocks will soon reach the market; in Europe, the AQuRA project (No101080166 EU Horizon Europe RI programme) consortium is currently building a prototype for an industrial grade transportable Sr clock. The AQuRA consortium comprises several leading European companies in laser technologies and quantum sensors, together with several academic participants of the CoCoRICO project who will be sharing their expertise in optical lattice clocks. The AQuRA project, industrial stakeholders and end-users aiming at developing field deployable clocks (such as in the field of geodesy (characterization of the Earth gravitational potential with accurate clocks with improved accuracy) and the generation of optical time scales (replacing microwave time scales with the advent of a new definition of the SI second)). These groups will directly benefit from the knowledge and expertise acquired during the CoCoRICO project which will allow the development of more accurate clocks (e.g. with reduced background gas collision uncertainty) and new trapping configuration (e.g. dead time free clock based on conveyor belt to avoid bulky laser stabilization). To ensure this, the project participants will organise a joint workshop with the AQuRA project, as well as workshops for stakeholders to disseminate the project results to support the implementation of novel trapping strategies developed in this project to industrial groups and end-users.

In addition, the spectral purity of the trapping laser is a critical characteristic for the accuracy of optical lattice clocks. The participant have developed calibration methods to evaluate the suitability of various trapping laser sources for high accuracy OLCs. This project will reinforce this capacity through building up the acquired knowledge about lattice light shift systematic effects. This is of particular interest for manufacturer of transportable OLCs systems, or spatial clocks such as ESA, who has already shown interest in this topic in the past.

Outcomes for the metrology and scientific communities

The outcomes of this project will have a direct impact on the time and frequency metrology community, by advancing the knowledge about OLCs, their characterization techniques, and by producing comparison data of clock frequency ratios. These outcomes will also directly contribute to the fulfilment of the roadmap towards the redefinition of the SI second. Specifically, the project participants will publish guidelines and papers on the developed new methods for improving the accuracy of OLCs, which will provide the community with new data for correcting for systematic effects, such as background gas collisions. In addition, clock comparison data will be published, and TAI calibration contributed to the BIPM.

The outcomes of the project (guidelines and papers about the development of new confinement strategies) will also be of interest to the broader quantum technology community, in which these techniques are used to manipulate and address individual atoms, sometimes using the narrow resonances originally studied for time and frequency metrology.

Finally, the data sets produced by optical clock comparisons will provide material for improved tests of fundamental physics, including the search for variations of fundamental constants and the search for dark matter.

Outcomes for relevant standards

This project targets two specific standard committees:

The Working Groups of the CCTF and CCL that are involved in monitoring and exploiting the progress of optical clock technologies, and in validating the criteria fulfilment of optical clocks before the redefinition of the SI second. The new systematic evaluation of OLCs performed in this project, the clock comparisons to validate this systematic evaluation and roduce new frequency ratio measurements and TAI calibrations, are therefore of high interest for these WGs. The project participants are often members of these working groups, or in close collaboration with them, and will benefit from this experience to promote the project outcomes to the relevant WG. To this aim, they will send reporting notes in preparation for the WG meetings.

Furthermore, the EURAMET European Metrology Network (EMN) for Quantum Technologies provides active coordination of European measurement science research to maintain competitiveness in the field of quantum technologies. Optical lattice clocks, as quantum sensors, are key tools in this field. The objectives of this project, especially on tailored and reconfigurable potentials (Objective 1) and hybrid cavity systems able to generate entanglement (Objective 2), are particularly relevant to the EMN-Q, and the associated project outcomes will be reported to this committee. The participants will present the project outcomes at the general assembly of the EMN-Q.

Longer-term economic, social and environmental impacts

According to the Key Performance Indicators of the European Quantum Flagship, a 150 % growth of market uptake of quantum technologies is expected by the end of the decade. This project, and the close relation between its participants and the relevant companies, is expected to directly contribute to this growth in the domain of quantum sensing. Furthermore, this project is relevant to the quantum computing and simulation domains, through the trapping and probing that the project participants will develop, and which are applicable to controlling and manipulating individual quantum systems. These domains, although not as mature today, are expected to have similar market uptake by 2030.

In environmental impact, and in specific in geodesy, the availability of high performance, repeatable and inter-connected optical frequency standards will allow geophysicists to monitor, with unprecedented accuracy, mass redistribution processes within the Earth. This will be possible through an improved system of vertical references at continental scales, which are currently unreachable by smooth satellite data or local gravity measurements. The applications of such improved vertical references range from seismic modelling, prediction of volcanic eruptions, to real time ground water and sea level monitoring. In addition, such data provides critical input into models used to study and forecast the effects of climate change.