Chinese crystal ‘paves way’ for GPS-free thorium clock navigation

Scientists in Xinjiang, China, have developed a novel crystal that produces ultraviolet light at a record-breaking 145.2 nanometres. This fluorinated borate compound surpasses previous benchmarks and meets a critical requirement for developing portable thorium nuclear clocks. These clocks, currently being developed in the United States, China, and other locations, could potentially enable GPS-free navigation for submarines and deep-space probes. The new crystal overcomes limitations of existing materials, like potassium beryllium fluoroborate, which could only reach 150nm. This achievement, reported in January in Advanced Materials, represents a significant step towards creating ultra-precise and independent navigation systems.