realization of Highly coherent and accurately frequency tunable light sources at ultraviolet region using semiconductor lasers.

为了提高非线性光学频率变换的基频光功率，提出了相干叠加技术。通过将这种技术应用于半导体激光器，这些激光器之间的相位误差减小到0.25拉德。在252 nm处实现了相干光的产生，用于硅原子俘获和单原子晶体生长。为此，进行了钛宝石激光器与其二次谐波和频的实验研究。利用非线性光学晶体LBO产生二次谐波，并设计了一个组合式光学腔，提高了二次谐波的产生效率。采用非线性光学晶体BBO产生和频，获得了大于50的建立因子和12 mW的二次谐波输出。对光学系统进行了优化设计，以调整基波和二次谐波的光束轮廓。结果获得了2.8nW的输出功率。虽然这个功率看起来很低，但对于捕获少量的原子来说，它是足够高的，这一点通过计算空芯光纤引导原子的势能得到了证实。光频梳发生器是调制产生的紫外光相位的重要器件，我们制作了多个光腔和波导。输出功率提高了15dB，并且调制边带的总跨度扩展到10THz。此外，为了保证梳状振荡器的可靠工作，还对调制边带之间的相位锁定和腔长的稳定进行了研究，以上结果表明，我们达到了本研究的目的。

TecHnique of coherent addition was developed to increase the fundamental laser light power for nonlinear potical frequency conversion. By applying this technique to semiconductor lasers, the phase error between these lasers was reduced to 0.25 rad. Addition efficiency was increased up to 85%, which is, to our knowledges, the highest record in the world.Coherent light generation at 252 nm was carried out for Silicon atom trapping and single atomic-level crystal growth. Experiments on generating the sum-freQuency between a titanium-sapphire laser and its second-harmonics was carried out for this purpose. A nonlinear optical crystal, LBO,was used for the second-harmonics generation, for which a build-up potical cavity was designed and used to improving the generation efficiency. The build-up factor of larger than 50 was realized and the second-harmonics power of 12 mW was obtained.A nonlinear optical crystal, BBO,was used to generate the sum-frequency. The potical system was potimized to tailor the beam profiles of the fundamental and second-harmonics waves. As the result, the output power of 2.8 nW was obtained. Although this power looks low, it is sufficiently high for trapping a small number of atoms, which was confirmed through calculating potical optential for atom-guiding by a hollow optical fiber.Multiple optical cavity and waveguide were fabricated for the optical frequency comb generator, which is an essential device for modulating the phase of generated ultraviolet light. The output power was increased 15 dB., and the total span of modulation sidebands was expanded to 10 THz. Furthermore, the phase-locking between the modulation sidebands, and stabilization of cavity length was carried out for reliable operation of the comb generator.By the results described above, it was confirmed that the we have reached the goal of the present research.