China marks nuclear clock advance with world-first 148 nm laser
A Chinese research team has achieved a breakthrough in nuclear clock development by creating the world’s first 148-nanometre continuous-wave ultra-narrow-linewidth laser in the vacuum ultraviolet (VUV) region, overcoming a long-standing technological bottleneck, TV BRICS reported.
According to Global Times, the advance marks the first successful extension of ultra-stable laser technology into the vacuum ultraviolet band – widely regarded as the “last core bottleneck” in nuclear optical clock research.
A nuclear clock is a next-generation timekeeping system that measures time by triggering transitions within the thorium-229 nucleus using vacuum ultraviolet lasers. Frequency comb technology is then used to count electromagnetic oscillations with extreme precision. In theory, such clocks could achieve an accuracy exceeding 10⁻¹⁹ – equivalent to gaining or losing less than one second over 300 billion years.
According to the source, nuclear optical clocks are expected to offer even greater stability and resilience to environmental disturbances. The Chinese team introduced an innovative approach based on four-wave mixing in metal vapour, enabling continuous-wave laser output at 148 nm.
By reducing the laser linewidth by nearly six orders of magnitude, the researchers established a technical foundation for ultra-stable VUV lasers and secured a critical first international breakthrough in this specialised domain.
Beyond advancing nuclear clock research, the new laser platform is expected to support developments in atomic clocks, quantum information science, autonomous navigation systems, and deep-space exploration.
As Qazinform News Agency reported on Monday, an earthquake hit China.
