Core Viewpoint - The article discusses the significant advancements in nuclear optical clock technology, particularly the development of a continuous-wave narrow-linewidth vacuum ultraviolet laser source, which addresses a critical bottleneck in the field [2][3][4]. Group 1: Technological Breakthrough - The Tsinghua University team successfully developed a 148 nm continuous-wave ultra-narrow linewidth laser source, overcoming the last core bottleneck in nuclear optical clock research [3][4]. - This laser source outputs power exceeding 100 nW and has a linewidth significantly lower than 100 Hz, with continuous tunability in the 140 to 175 nm range, which is crucial for the development of thorium-229 nuclear optical clocks [3][6]. Group 2: Strategic Importance - Nuclear optical clocks, utilizing nuclear transitions instead of electronic transitions, are expected to provide higher precision and better environmental disturbance resistance, making them a strategic frontier in quantum precision measurement [2][4]. - The advancements in laser technology not only facilitate the development of nuclear optical clocks but also support various cutting-edge scientific applications, including quantum information experiments and high-resolution spectroscopy [7]. Group 3: Future Implications - The new laser source platform is anticipated to enhance the resilience of key segments in the semiconductor industry by supporting vacuum ultraviolet metrology and chip testing [7]. - The research findings lay the groundwork for further advancements in coherent vacuum ultraviolet light sources, potentially leading to higher performance metrics in various applications [6][7].

北京市一支年轻的科研团队，在实验室内成功发出波长仅148纳米的连续激光，攻克了核光钟研制的最 后一个核心瓶颈，并首次将超稳激光技术拓展至真空紫外波段。依托这项技术，未来，人类对时间的精 密计量能力将有望再上台阶。2月12日，这项成果登上《自然》杂志。 时间计量离不开高精度"振荡器"。全国通用的"北京时间"，是依靠高性能原子钟组通过精密比对和校准 实现的。原子钟的原理基于原子外层电子跃迁，但外层电子对电磁场环境比较敏感，一旦受到外界影 响，频率就会发生改变，影响计时精度。最高精度的原子光钟通常只能在实验室环境内运行。 科学界提出了一条更具潜力的路径——核光钟。钍-229原子核激发态能量最低，最容易被激光激活，它 的原子核内部跃迁可以成为计时的参考。原子核跃迁对外部环境的敏感性更低，这让核光钟的工作环境 限制更小，更加简易、便携，且测量精度有望进一步提升。"不过，这些只是学术界的展望，因为核光 钟的研制面临一个核心瓶颈，那就是产出能操控钍-229原子核的148纳米连续激光。"清华大学副教授、 北京量子信息科学研究院兼聘研究员丁世谦带领团队，向这一难题发起挑战。 实验室里，一个意想不到的现象出现。"蒸气内的原子密度 ...