Kiyohide Sakai

酒井 清秀

Creative Repository of Electro-Communications

導波路型緑色高調波発生システムの高出力化に関する研究

In this dissertation, we discuss the results of the study on high-powersecond-harmonic generation (SHG) devices consisting of a channel waveguideand a planar waveguide and on a semiconductor laser as a source of thefundamental wave.This dissertation is divided into five chapters. The first chapter introduces thisstudy by describing its background and purpose.The second chapter discusses the design of a quasi-phase-matched SHG devicewith a channel waveguide and the experiment performed on the device; theridge-type channel waveguide consisted of a periodically poled5-mol%-MgO-doped LiNbO3 (PPMgLN) core and SiO2 claddings. During theexperiments, to prevent higher-mode and leaky-cladding-mode oscillations inthe multimode waveguide, we employed Gaussian-beam impingement on aright-angled waveguide with an antireflection coating on its surface. A greenlight with a power of 360 mW and a conversion efficiency of 38% was obtainedat room temperature by using an 8.3-mm-long SHG device. However, this resultwas obtained with a high waveguide loss of 66 m－1 and the observation of atemperature gradient along the waveguide.To overcome the above drawbacks, we carried out experiments on aquasi-phase-matched SHG device with a planar waveguide; the design andexperimental details of this device are described in the third chapter. The use ofthe Y-cut PPMgLN planar waveguide, which was mounted waveguide-sidedownward to the heat sink, resulted in a low waveguide loss of 2 m－1, low heatresistivity, and a wide area of heat radiation. In these experiments, a green lightwith a power of 1.6 W and a conversion efficiency of 40% was obtained atroom temperature by using a 7-mm-long SHG device.In the fourth chapter, we report the experimental results of a master oscillatorpower amplifier (MOPA), in which a planar-type tapered semiconductoramplifier was injected with a seed light through a biconical microlens. In theseexperiments, a 3-mm-long tapered amplifier with an optical confinement factorof 1.2% was found to output a power of 5.5 W with a beam quality factor (M2)of 1.5.Finally, the fifth chapter concludes the study.電気通信大学200

https://uec.repo.nii.ac.jp/?action=repository_action_common_download&item_id=1156&item_no=1&attribute_id=20&file_no=1

導波路型緑色高調波発生システムの高出力化に関する研究

Abstract

Similar works

Full text

Available Versions

Creative Repository of Electro-Communications

Creative Repository of Electro-Communications