'Phase Transition' in the 'Thorium-Isomer Story'

TL;DR

This paper reviews recent progress in understanding the thorium-229m isomer, emphasizing the transition from nuclear physics research to laser physics applications aimed at developing a nuclear clock.

Contribution

It summarizes current knowledge and recent achievements, outlining the next steps towards realizing a nuclear frequency standard based on thorium-229m.

Findings

Significant progress in decay and nuclear property measurements

Shift from search phase to realization phase for nuclear clock development

Identification of key next steps towards a nuclear frequency standard

Abstract

Given the drastic progress achieved during recent years in our knowledge on the decay and nuclear properties of the thorium isomer 229mTh, the focus of research on this potential nuclear clock transition will turn in the near future from the nuclear physics driven `search and characterization phase' towards a laser physics driven `consolidation and realization phase'. This prepares the path towards the ultimate goal of the realization of a nuclear frequency standard, the `Nuclear Clock'. This article briefly summarizes our present knowledge, focusing on recent achievements, and points to the next steps envisaged on the way towards the Nuclear Clock.