Fabrication of ZnO Micro-Sphere Whispering-Gallery-Mode Ultraviolet Laser and Their Applications

2015 Fiscal Year Final Research Report

• Project/Area Number: 25286071
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Optical engineering, Photon science
• Research Institution: Kyushu University
• Principal Investigator: OKADA TATSUO 九州大学, システム情報科学研究科(研究院, 教授 (90127994)
• Co-Investigator(Kenkyū-buntansha): Nakamura Daisuke 九州大学, 大学院システム情報科学研究院, 准教授 (40444864)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 酸化亜鉛 / ZnO / 微小球 / WGM / p-n接合 / レーザーアブレーション

Outline of Final Research Achievements

ZnO micro-spheres were synthesized by laser ablation in air using a Q-switched Nd:YAG laser and a normal-mode Nd:YAG laser, and their optical properties were characterized.
In order to realize p-type ZnO micro-spheres, P-doped ZnO micro-spheres were synthesized. When a heterojunction was made with P-doped ZnO micro-sphere and Al-doped n-type ZnO thin film, apparent rectifying I-V characteristics was observed. In order to control the lasing wavelength of ZnO micro-sphere, Mg doped ZnO micro-spheres were synthesized. When 5 wt% of Mg was doped, the lasing wavelength was 370 nm, which was shorter by 25 nm, compared with 395 nm for non-doped micro-spheres. We have obtained the UV EL emission from p-n junction consisting of Mg-doped ZnO micro-sphere and p-type GaN thin film.
In order to apply ZnO micro-spheres to sensor system, we have investigated the dependence of the lasing wavelength of ZnO WGM laser on the refractive index of the surrounding material experimentally and theoretically.

Free Research Field

総合理工