埋覆式量子點雙微碟共振腔之迴音廊模態分裂現象

Mode Splitting Behavior of Whispery Gallery Modes in Coupled Microdisks with Embedded Colloidal Quantum Dots

羅家彬(Chia-Pin Lo)

指導教授 ： 毛明華

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2013年)

https://doi.org/10.6342/NTU.2013.01635

摘要

我們已經成功製作出埋覆式膠狀量子點的二氧化矽微碟，並能夠以光激發的方式操作在波長約為605奈米的可見區，且能有很高的Q值。以此為基礎製作兩尺寸相近的二氧化矽主動微碟，並以110奈米、150奈米以及200奈米的間隙排列，而我們也能夠在室溫下量測到此結構的迴音廊模態。
在此論文中，我們將觀察間隙為110奈米、150奈米以及200奈米雙碟的模態分裂情形。在我們的量測系統中，使用了Nd:YAG固態雷射作為激發光源，而Ti:sapphire雷射作為加熱光源使其中一個微碟的迴音廊模態發生藍移現象。我們可以使來自兩微碟的兩模態波長位置漸漸靠近，當無法繼續靠近時，我們推測此現象為雙碟耦合效應所引發的模態分裂。在實驗中，間隙為110奈米、150奈米以及200奈米雙碟我們量測到0.45奈米、奈米0.61和0.71奈米的模態分裂現象。為了證實我們利用程式模擬間隙為100奈米、150奈米以及200奈米雙碟其模態分裂理論上應為0.4奈米、0.58奈米以及0.77奈米。就趨勢上來看是相當吻合的。

關鍵字

微碟雷射 ； 量子點 ； 模態分裂

並列摘要

Silicon dioxide microdisks embedded with CdSe/ZnS colloidal quantum dots were demonstrated in the visible range around 605 nm, and they exhibit high Q-factor operation by optical pumping. We also fabricated the coupled microdisk structure consisting two nearly identical silicon dioxide microdisks with gaps of 110nm, 150nm and 200nm respectively and embedded with colloidal quantum dots. The WGMs (whispery gallery modes) have also been observed at room temperature.
In this thesis, we investigate the mode splitting behavior of coupled microdisks which are spaced by 100nm to 200nm separation. In micro-photoluminescence setup, we use a Nd:YAG solid state laser as excitation and a Ti:sapphire laser as heating source, leading to blueshift of WGMs of one microdisk. Clear mode splitting can be observed when making the two WGMs keep closing continuously until they stop. We found mode splitting in 0.45nm, 0.61nm and 0.71nm experimentally and 0.4nm, 0.58nm and 0.77nm theoretically by simulation with gaps of 110nm, 150nm and 200nm.

並列關鍵字

microdisk laser ； quantum dot ； mode splitting

參考文獻

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