本論文主要研究與發展具有三明治結構之可電控聚合物穩定膽固醇液晶(Polymer-stabilized cholesteric liquid crystal，PSCLC)複合雷射。此雷射樣品包含三層結構，中間層為染料摻雜向列型液晶(Dye-doped nematic liquid crystal，DDNLC)，兩側為PSCLC層。中間層的染料具有增益介質功能，外側的PSCLC層作為分佈式布拉格反射鏡，被激發光源所激發的螢光可被兩側PSCLC反射於DDNLC增益層中達到共振條件，進一步在數個共振模態競爭中產生雷射閾值最低之雷射輸出。
實驗結果發現，以強紫外光聚合完成的PSCLC樣品不僅產生聚合物網絡穩固住空間中膽固醇液晶的螺旋結構，且隨之產生許多離子雜質。在外加直流電壓時，這些離子重新分佈導致PSCLC樣品內部產生螺距梯度，進而達到反射波帶大量變寬效果。另外，中間DDNLC層除染料有增益效果，液晶則具有波板效果，做為半、全波板時，於元件反射波帶內之反射率分別為相對極大值與極小值，雷射共振模態將會在反射率相對極小值時獲得。當外加相同直流電壓於兩側之PSCLC樣品時，反射波帶增寬會造成共振模態數量的增加，等效於反射波帶兩側共振模態在頻譜上可往外位移，當施加的電壓越高則兩側共振模態的位移量會越大，此時所產生的雷射輸出波長也會以跳躍式的方式位移。
此外，本論文也同時電控兩側的PSCLC層及中間的DDNLC層，共振模態也會因為電控DDNLC層而跟著細微變化，以至於雷射輸出波長可調程度可以更加細微，也增加了雷射輸出訊號的數量與調控的細緻度。

This thesis demonstrates an electrically tunable polymer-stabilized liquid crystal (PSCLC) composite laser with a sandwich structure, including the dye-doped nematic liquid crystal (DDNLC) layer in the middle and the PSCLC layers at two sides. The dye in the middle layer functions as a gain medium, and the set of the outer PSCLC layers serves as a distributed Bragg reflector. The fluorescence emission excited by the pump laser can be reflected by the PSCLC reflectors to reach resonance conditions and further enhanced in the DDNLC gain layer to produce the laser output with the lowest lasing threshold at the competition of several resonance modes. Experimental results show that the photopolymerization of the PSCLC layers in the composite laser produces a polymer network to stabilize the helical structure of the planar CLC and yields many ionic impurities. When a DC voltage is applied to the PSCLC layers, the redistribution of the ions results in a pitch gradient in the layers and then causes the broadening of the reflection band of the PSCLC layers. The dye in the middle DDNLC layer has a gain effect and a wave plate effect. When the DDNLC layer is used as a half- and full-wave plate, the reflectivity in the reflection band of the composite sample will have relatively maximum and minimum values. The laser resonance mode is obtained when the reflectivity is relatively the highest. When the DC voltage is applied to the PSCLC layers, the broadening of the reflection band can increase the number of resonance modes accommodated in this band. When the applied voltage is higher, the generated laser output wavelength will shift more in a stepwise manner in spectrum. The application of an AC voltage on the DDNLC layer can achieve the fine-tuning of the laser output wavelength.

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