光激發鈣鈦礦量子點塔米電漿雷射

Abstract

本論文以金屬/布拉格反射鏡構成的塔米電漿結構取代常見的兩對高反射率的分散式布拉格反射鏡構成的共振腔，塔米電漿結構擁有較好的侷限性，得到高品質因數的共振腔，而高量子效率與高激子束縛能(38 − 60 meV)的全無機鈣鈦礦量子點非常適合嵌入在塔米電漿侷域性強電場的空間中，藉此探討在室溫下塔米電漿子與鈣鈦礦量子點激子耦合，產生極化子凝聚效應之研究。使用μ-PL量測TP雷射結構樣品(Ag /鈣鈦礦量子點 /DBR)，發現入射光從頂部Ag方向進入，從光譜圖發現在激發雷射閾值約為5.16 MW / cm2，波長約530-540 奈米處有隨機雷射的作用，而在波長約550奈米的地方，觀察到樣品有極化子發射的現象，但是因為極化子與光子模態不相符，因此沒有產生極化子雷射的作用。另外入射光從底部DBR方向進入，只有觀察到激發雷射閾值為〜0.897 MW / cm2，波長約530-540 奈米處有隨機雷射的產生，其原因為雷射激發源的入射方向更改為樣品底部時，Ag /鈣鈦礦量子點界面處的局部電場激發太弱，以至於其強度不足以激發極化子發射，另外將DBR與鈣鈦礦量子點製作成OLED元件，從光電流分析其亮度較一般玻璃基板製作的OLED其亮度提高3.8 %In this thesis, we use Tamm plasmon structure composed of metal/Bragg mirrors in order to replace the resonant cavity which composed of two high reflectivity dispersed Bragg reflectors . The Tamm plasmon structure has good limitations can lead to a high Q-factor resonant cavity . The all-inorganic perovskite quantum dots provides high quantum efficiency and large binding energy (38 − 60 meV) . Which are very suitable for embedding into the space of strong localized electrical field of Tamm plasmon. This is to explore strong coupling between Tamm plasmon mode and perovskite excitons, and to discovery of new exciton-polariton effect. Use μ-PL to measure TP laser structure samples (Ag/Perovskite quantum dots/DBR), Incident direction of pumping laser, i.e. from the top side (Ag) of the sample. I observe several spectral spikes in the wavelength regime of 𝛌 =530-540 nm, due probably to the aggregation of perovskite QDs which scatters emitted photons to stimulate random lasing actions with pumping threshold of ~5.16 MW/cm2, also observe the possible polariton emissions at 𝛌 ~ 550 nm on our samples, but there is no polariton lasing actions due probably to the large detuning of exciton and photonics mode. When change the incident direction of pumping laser, i.e. from the bottom side (DBR) of the sample. Again, the random lasing actions with the pumping threshold of ~0.897 MW/cm2 can still be observed in 𝛌 =530-540 nm; however, there is no occurrence of polariton emission in 𝛌 ~ 550 nm. Because the localized electrical field at the Ag/perovskites QDs interface was weakly excited, and hence its intensity is insufficient to stimulate polariton emissions. In addition, DBR and perovskite quantum dots are made into OLED components, according to the analysis of photocurrent, its brightness is increased by 3.8% compared with that of OLED made of glass substrate.