在本論文裡，作者利用雷射染料分子-羅丹明6G (Rhodamine 6G, R6G)搭配銀奈米棱柱體 (Silver nanoprisms, Ag NP)放置於聚醯亞胺 (Polyimide, PI)軟性基板上作為樣品的實驗組；單純R6G染料分子在PI基板上作為對照組。在Nd:YAG脈衝雷射的激發下，我們發現僅有實驗組的樣品會產生隨機雷射的現象；此外，我們還發現實驗組樣品在PI基板隨著外力作用下其形變會導致誘發出的隨機雷射波長產生藍移現象。藉由實驗觀察到的隨機雷射發光機制在本論文進行討論，作者推測其雷射的共振來自於Ag NP的表面電漿共振。此外，我們還藉由顯微鏡暗場量測Ag NP的散射光譜。透過彎曲PI基板，作者觀察到其散射光譜有藍移情形，推測是因為彎曲基板導致在上面的Ag NP其間距變大所致，該結果與彎曲實驗組樣品誘發出的隨機雷射波長藍移的現象一致。相較之下，對照組的樣品在脈衝雷射的激發下，僅產生自發輻射，其發光波長亦不受基板彎曲而影響。其結果再次印證Ag NP在PI可撓式基板上與R6G分子電漿耦合誘發出波長可調之隨機雷射的可行性，預期Ag NP在隨機雷射的應用方面可以開闢出一新的領域，搭配含有R6G的PI基板發展出具有新穎性的發光隨機系統。

In this thesis, the author described random laser operation of two samples, i.e., PI films containing R6G without the silver nanoprisms, and PI films including R6G with the silver nanoprisms. As expected, random lasers have been observed only for the samples containing the silver nanoprisms. The author validated that the lasing oscillation arises mainly from surface plasmon resonances induced by the silver nanoprisms, which enhances the scattering strength of emitted photons to achieve the population inversion required for the stimulated emission. More importantly, the effects of bending samples on the wavelength tunability of random laser were systematically studied and discussed. With the increasing of bending degree of PI substrate, it was found that the oscillation profile of reflective scattering spectrum measured on the silver nanoprisms is blue-shifted monolithically, yet it still covers the entire gain curve of R6G. Hence the random laser emission can be controlled by means of the simple bending of PI substrates. The fundamentals responsible for the observed tunable lasing emissions were also illustrated. As a result, we believe that the demonstration of tunable lasing emissions induced by the silver nanoprisms dispersed on the flexible PI substrate is expected to open up new route for the applications of disorder based optoelectronic devices.

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