低臨界功率二維光子晶體雷射

Low threshold two dimensional photonic crystal laser

李嘉祥(Chia-Shiang Li)

指導教授 ： 徐子民

國立中央大學/理學院/物理學系/碩士(2008年)

摘要

本論文是探討光子晶體雷射的光學特性，首先我們會經由螢光偏振量測和模擬計算相互對照，區辨出qL2共振模態的偏振方向和電場強度分佈情形。接下來利用微螢光量測系統(μ-PL)，量測不同空氣孔洞半徑的qL2共振腔，並且將實驗結果與平面波展開法模擬數據相比較，根據兩項結果，篩選出最適合雷射研究的模態和qL2共振腔的幾何結構。 雷射研究是在室溫(300K)和低溫(10K)下進行量測，利用不同功率的連續波(continuous wave ,CW)光源激發光子晶體元件中的量子點，在低溫下螢光光譜結果呈現雷射的特性，包含雷射模態的半高寬變窄和螢光強度增強，並且分析實驗數據得到低的臨界功率~500nW和高的β值~0.85，最後深入探討β值和臨界功率的關連性。經由我們的研究可論證量子點在光子晶體共振腔內，可應用在製作低臨界功率的紅外光雷射。

關鍵字

光子晶體雷射

並列摘要

In this paper, we will investigate the optical properties of photonic crystal laser. According to polarization measurement results comparing with simulation calculations, we can define polarization direction and electric field intensity distribution of qL2 cavity mode. By micro-photoluminescence (μ-PL) measuring in different air hole radius of qL2 nanocavity, and experiment results were compared with the theoretical calculations results using plane wave expanded method (PWEM). We found most suitable cavity mode and geometry structure of qL2 cavity which is based on experiment and theory results to study lasing experiment.
We employ continuous-wave laser in different pumping power to excite quantum dots with qL2 nanocavity in 300K and 10K. Experimental results assumed many lasing characteristics which included full width at half maximum (FWHM) of lasing mode narrowing and intensity increasing in 10K. By analyzing lasing experiment data, we can obtain low threshold power~500nW and high β value~0.85. Finally we will consider correlation about threshold power and β value. Our experiments demonstrate that the quantum dots emission in photonic crystal nanocavity can be applied to the fabrication of low-threshold infrared laser.
ii

並列關鍵字

Photonic crystal laser

參考文獻

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