本論文探討單一氧化鋅微共振腔在使用角度解析光激發發光技術下所產生室溫中的激子極化子現象。使用碳熱還原氣相轉移法所生長的一維氧化鋅微共振腔結構擁有六角柱的形貌可作為耳語迴廊模態共振腔，同時氧化鋅亦可作為雷射的增益介質。光子會在六角柱的橫截面上進行多次的氧化鋅/空氣介面全反射並被侷限在微共振腔中。因此，氧化鋅中的激子便能與耳語迴廊模態共振腔的光子強耦合產生激子極化子。由於微共振腔中激子與共振腔光子的強交互作用，在低載子密度的連續波長雷射激發下激子極化子的色散曲線可觀察到反交叉現象。而在高載子密度的脈衝雷射激發下，我們觀察到激子極化子的雷射現象伴隨著波峰藍移的現象產生。隨著激發強度增加，角度解析光激發發光譜展示出激子極化子藉由極化子之間的散射，由高能量區域馳豫到低能量區域並且聚集在激子極化子的能量基態。此種激子極化子的聚集現象實現了室溫中的波思-愛因斯坦凝聚現象並形成一種新型態的激子極化子雷射。

We demonstrate the effects of exciton-polariton in a ZnO microcavity investigated by angle-resolved micro-photoluminescence spectroscopy at room temperature. The one-dimensional hexagonal ZnO microcavities synthesized by vapor phase transport method provide an optical cavity of whispering gallery modes (WGMs) and laser gain medium as well. The photon propagates in the hexagonal cross section plane as a result of multiple total internal reflections at the ZnO/air interface. Therefore, the exciton of ZnO strongly coupled to the WGM can form exciton-polariton. The polariton presents the anticrossing behavior in energy momentum diagram showing the strong interaction between exciton and cavity photon existed inside the ZnO microcavity under low carrier density excitation. Upon pulse laser pumping, we observe lasing action of the emission peaks and the blueshift of the polariton modes. An exciton-polariton condensation is also observed at room temperature throughout the power-dependent angle-resolve photoluminescence spectra.

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