高品質因子與低模態體積光子晶體微共振腔之設計與製作

Design and Fabrication of High Quality Factror and Low Mode-Volume Photonic Crystal Micro-cavities

曾彥鈞(Yen-chun Tseng)

指導教授 ： 綦振瀛

國立中央大學/理學院/光電科學研究所/碩士(2007年)

摘要

近年來，光子晶體微共振腔儼然成為光電元件研究領域中最重要的課程，人們也對 於光子晶體擁有應用在雷射與單光子源發射器得天獨厚的優勢產生濃烈的興趣。其中， 如要製作優良的光子晶體元件，無論是雷射或單光子源發射器元件，高品質因子與低模 態體積共振腔體的目標是我們一路上所追求與渴望的。然而，在本研究中我們設計ㄧ個 共振腔結構，並已製作出砷化鎵薄片光子晶體微共振腔元件。設計結構的方式，我們是 在六角排列的週期性晶格中改變兩個空氣柱直徑尺寸與位置而形成缺陷區域，這樣的結 構相似於傳統H1 點缺陷結構，因此我們將之命名為quasi-H1 結構(縮寫qH1 結構)。qH1 結構在我們利用二維有限時域差分法計算之水平品質因子高達約400,000 以及三維有限 時域差分法計算模態體積僅有0.011 μm3。 根據模擬結果，我們實際製作了一系列的光子晶體微共振腔於砷化銦量子點為主動 層的砷化鎵薄片上，其室溫品質因子可高達近4000，這是H1 光子晶體結構中世界最高 值。利用這些樣品我們將光子晶體參數(包含晶格常數和空氣柱尺寸)與品質因子間的關 係，亦作了系統性的研究與探討。

關鍵字

共振腔 ； 光子晶體 ； 模態體積 ； 品質因子

並列摘要

In recent years, photonic crystal micro-cavity has been a subject of great interest for
various optoelectronic devices, such as lasers and single photon emitters. For the latter
application, cavities with high quality factor and low mode-volume are most desirable. In this
study, we design and fabricate GaAs photonic crystal membranes with a hexagonal lattice
structure. A defect region is created by changing the diameter and location of the center two
air holes of the lattice structure. Using two dimensional frequency-domain-time-difference
simulation, a cavity with high quality factor (~400,000) and low mode-volume (~0.011μm3) is
designed.
A series of GaAs photonic crystal membranes with embedded InAs quantum dots has
been fabricated accordingly. Quality factors as high as 4000 at room temperature are
measured on the sample with an air hole diameter of 260 nm and distance of 450 nm. To the
best of our knowledge, this is the highest value reported for H1 photonic crystal cavities. The
correlation between the quality factor and lattice parameters is investigated systematically.

並列關鍵字

mode volume ； photonic crystal ； cavity ； qH1 ； quasi-H1 ； quality factor

參考文獻

[16] Maria Makarova, Jelena Vuckovic, Hiroyuki Sanda, and Yoshio Nishi,

[1] E. Yablonovitch, “Inhibited Spontaneous Emission in Solid-State Physics and Electronics”, Phy. Rev. Lett., 58, 2059(1987)

[2] S.John, “Strong localization of photons in certain disordered dielectric superlattices”,Phy. Rev. Lett., 58, 2486(1987)

[3] E. Yablonovitch, “Photonic crystals: semiconductor of light”, Scientific American December,47(2001)

[4] E. Yablonovitch, et. al. “Photonic band structure: The face-centered-cubic case employing nonspherical atoms”, Phys. Rev. Lett. 67, 2295(1991)