寬能隙(3.37 eV)之Ⅱ-Ⅵ族半導體材料氧化鋅，具有較大之激子束縛能(~60 meV)，此特性使激子能於室溫存在於氧化鋅中，並且氧化鋅之六角形微柱可以作為侷限光子之微共振腔結構。綜合上述兩個特性，激子與光子能夠於氧化鋅微奈米柱中發生強烈的交互作用，進而在室溫下產生激子極化子。但是若要將激子極化子等應用推廣至實際光電元件，我們必然需要完全了解氧化鋅微奈米柱之材料性質，其中一項最重要的材料性質為折射率，是不同激子極化子模態於氧化鋅內傳遞時應謹慎考慮的問題。
因此我們在此論文中提供一種簡單的方式來獲得我們氧化鋅微米柱本質折射率。一般強耦合下之激子極化子色散情形常用半古典羅倫茲模型來描述，然而許多團隊會將背景折射率設定為定值，這會造成拉比分裂能量的誤判。因此我們進行羅倫茲模型的修正以符合實際情況之折射率。在可見光部分折射率我們參考其他團隊使用橢偏儀量測氧化鋅單晶塊材之結果，並對其以柯西色散公式擬合參數。在近能帶部分則利用耳語迴廊共振腔模態間距推算出該部分之折射率。以柯西色散公式帶入羅倫茲色散模型修正後，我們可以得到與激子極化子有關之參數，如拉比分裂能量與阻尼項等。最後我們可以由修正後之激子極化子色散公式得到消光係數與能量色散圖以外，還模擬激子極化子模態於角度解析光激發光光譜之色散曲線，其與實驗所量測之結果相當吻合。

We modify the formula of ZnO polariton dispersion relation in a strong coupling regime to match the “real” refractive index of ZnO microrod. The ZnO polariton dispersion relation in a strong coupling regime is in the form of the Lorentz dispersion model. There are some problems when the formula applying to the general cases, such as the background permittivity is constant and the damping constant is neglected. After substituting the Cauchy dispersion equation into the Lorentz dispersion model, we can extract some parameters relating to exciton-polariton, such as exciton resonance energy, Rabi splitting energy, and damping energy. By the formula of modified ZnO polariton dispersion relation, we can obtain the extinction coefficient of ZnO microrod, the exciton-polariton energy-dispersion diagram. We can also confirm the detuning of each exciton-polariton whispering-gallery mode. Furthermore, we simulate the dispersion curve of exciton-polariton modes in angle-resolved photoluminescence. By the formula of modified ZnO polariton dispersion relation, it coincides well with the measured results.

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