拉曼喷泉原子钟

Raman Atomic Fountain Clock

利用拉曼光场代替喷泉原子钟的微波腔实现拉曼喷泉原子钟。将分离拉曼光场技术与冷原子喷泉技术相结合,避免了在真空腔内放置微波腔,简化了真空系统,同时还保持了很高的准确度。采用半经典理论研究了冷原子喷泉与拉曼光场的相互作用过程,得到了冉赛(Ramsey)条纹。比较了拉曼喷泉原子钟与热铯束拉曼原子钟,前者有更小的体积和功耗,其精度可能达到或超过商用小铯钟。还比较了拉曼喷泉原子钟与微波喷泉原子钟的差别,分析了光子反冲的影响,提出利用同向传播和相向传播的两台拉曼原子钟测量精细结构常数。

An atomic fountain clock based on Raman laser field instead of microwave cavity is proposed. This scheme combines the separate Raman fields technology and the cold atomic fountain technology, cancels the microwave fountain clock in the vacuum cavity and meanwhile keeps a high accuracy. The interaction process of the cold atomic fountain and the Raman laser field is studied with the semiclassical theory and the Ramsey fringes are acquired. The Raman fountain clock is compared with the atomic beam clock of hot cesium atoms, and it is found that the accuracy of Raman fountain clock higher and its capacity and power consumption are much smaller. Compared with the microwave fountain clock, the Raman fountain clock must consider the influence of photon recoil. With the photon recoil, it is proposed to measure the fine structure constant by using two Raman fountain clocks.