Meijer T, White J D, Smeets B, Jeppesen M, Scholten R E
School of Physics, University of Melbourne, Victoria 3010, Australia.
Opt Lett. 2006 Apr 1;31(7):1002-4. doi: 10.1364/ol.31.001002.
We demonstrate production of continuous coherent blue laser light by using a five-level system in rubidium vapor. Two low-power lasers, at 780 and 776 nm, induce strong atomic coherence in the 5S-5P-5D states. The atoms decay to the 6P excited state, from which stimulated emission produces a coherent blue (420 nm) beam. We have coupled both ground-state hyperfine levels, effecting coherence between four levels. The coherent blue output is enhanced by several mechanisms, including stronger coupling to a larger fraction of the atomic population, operation at a detuning such that the vapor is nominally transparent to the 780 nm pump field, reduced losses owing to optical pumping, and optimal phase matching. We report experimental findings and compare them with results from a semiclassical Maxwell-Bloch model.
我们展示了通过在铷蒸汽中使用五能级系统产生连续相干蓝光激光。两台低功率激光器，波长分别为780纳米和776纳米，在5S - 5P - 5D态诱导出强原子相干。原子衰变到6P激发态，从该激发态通过受激发射产生相干蓝光（420纳米）光束。我们耦合了两个基态超精细能级，实现了四个能级之间的相干。相干蓝光输出通过多种机制得到增强，包括与更大比例的原子群体更强的耦合、在失谐状态下运行以使蒸汽对780纳米泵浦场名义上透明、由于光泵浦导致的损耗降低以及最佳相位匹配。我们报告了实验结果，并将其与半经典麦克斯韦 - 布洛赫模型的结果进行比较
