| 摘要: | 在本論文中，我們選用具有雙吸收峰的有機材料F8BT作為共振腔的主動層，建構出超強耦合共振腔架構。在該架構中，主動層同時擔任光子源以及激子源，這樣的設計使得我們能夠製作出具有更強耦合強度的元件，進而對其背後的物理現象進行詳細的探討。在共振腔中的光子與激子進行耦合作用時，會產生一種由光和物質所組成並有玻色子特性的混成態粒子，稱為偏極子。在具有雙吸收峰主動層的共振腔中，耦合作用會導致新的能量分支的形成，這些分支分別稱為上支、中支和下支。當共振腔中光子的能態與激子能態相同時，上支與下支之間的能量差被稱為拉比分裂。若拉比分裂大小超過激子能量的20 %時，則稱該共振腔達到了超強耦合。
在實驗開始前，我們會使用光學薄膜設計軟體Macleod來模擬各膜層的厚度，確保下支的位置正確對應到F8BT的光致發光PL位置，並且模擬出DBR布拉格反射鏡中的高低折射率材料的厚度。我們使用不同反射鏡的共振腔去探討其對耦合特性的影響，其中DBR布拉格反射鏡中心波長是設計在515 nm，高反射率頻寬僅包到F8BT的單吸收峰。最後結果得出不同反射鏡的共振腔均可以達到30 %附近的耦合強度，達到了超強耦合。使用不同功率的激發光源去激發DBR布拉格反射鏡共振腔，可以發現到隨著功率的增加，光譜上的能量會往低角度聚集，產生與雷射相同的特性。
;In this paper ,we selected the organic material F8BT,which has dual absorption peaks,as the active layer of the resonant cavity to construct a Ultra-strongly coupled cavity structure. In this setup , the active layer functions as both the photon and exciton source . This design allows us to fabricate devices with increased coupling strength,enabling a detailed investigation of the underlying physical phenomena . When photons and excitons within the resonator couple , they from a hybrid state particle composed of light and matter , exhibiting bosonic characteristics , known as a polariton . In resonators with a dual-peak active layer , the coupling leads to the formation of new energy branches , referred to as the upper、middle and lower branches . When the photon and exciton energy states in the resonator align , the energy difference between the upper and lower branches is called the Rabi splitting . If the Rabi splitting exceeds 20 % of the exciton energy , the resonator is considered to have achieved strong coupling .
Before the experiment begins , we utilize the optical thin film design software Macleod to simulate the thickness of each layer , ensuring the lower branch correctly aligns with the photoluminescence (PL) position of F8BT , and to model the thicknesses of high and low refractive index materials in the Distributed Bragg Reflector (DBR) mirrors . We use resonators with different mirrors to explore their effects on coupling characteristics , where the central wavelength of the DBR mirrors is designed at 515 nm , and the high reflectance bandwidth only covers the single absorption peak of F8BT . The results show that resonators with different mirrors can achieve a coupling strength of about 30 % , indicating strong coupling . By exciting the DBR resonators with light sources of varying powers , we observe that as power increases , the energy on the spectrum concentrates towards lower angles , exhibiting characteristics similar to those of a laser . |
