COALESCe - COmpAct Light Engines for Strontium Clocks

包括研究、国防和金融领域在内的大量应用都需要紧凑型光学时钟，以保持其准确性和可靠性，并降低成本和占地面积。光学时钟能够比当前的时间标准具有更好的稳定性和更低的不确定性;然而，每个时钟都需要一系列激光器，这些激光器对时钟核心的原子种类有着严格的要求。中性锶是应用最广泛的原子之一。它有一个关键的转变，必须使用发射波长为461 nm、功率> 1 W且线宽（光谱纯度）<32 MHz的激光源来解决。目前，研究人员必须使用昂贵或不足的激光源来满足这些要求。在本项目中，我们将在基于半导体磁盘激光器（SDL）技术的低成本、紧凑型系统中满足中性锶的所有上述要求。SDLs的有利特性，窄线宽操作先前已在实验室中得到证明;然而，它们的潜力toaddress感兴趣的波长的光学时钟，而且要实现这一点，在一个紧凑的商业格式，尚未实现。我们将设计一个稳定的窄线宽922 nm SDL，其频率加倍至461 nm，符合锶光钟系统所需的成本和体积参数，以从研究实验室中脱颖而出并解决该领域的应用问题。

A large number of applications, including those in research, defence, and finance require compact optical clocks that retaintheir accuracy and reliability for lower costs and footprints than existing systems. Optical clocks are capable of betterstability and lower uncertainty than the current standard of time; however, each clock requires a range of lasers withdemanding requirements specific to the atomic species at the heart of the clock. Neutral strontium is one of the mostwidely used atoms. It has a key transition that must be addressed using a laser source with emission wavelength at 461nm,power >1W and linewidth (spectral purity) <32MHz. Currently researchers must use expensive or inadequate lasersources to meet these requirements. In this project we will meet all the above requirements of neutral strontium in a lowcost, compact system based on semiconductor disk laser (SDL) technology. The advantageous properties of SDLs fortunable, narrow linewidth operation have previously been demonstrated in the laboratory; however, their potential toaddress wavelengths of interest for optical clocks, and moreover to achieve this in a compact commercial format, have yetto be realised. We will engineer a stabilised, narrow linewidth 922nm SDL with frequency doubling to 461nm within thecost and volume parameters required for strontium optical clock-based systems to emerge from the research laboratoryand address applications in the field.