本篇論文主要透過可改變旋性之手性分子馬達摻混向列型液晶(E7)，首次發展出可全波長調控且可圓偏振反轉之新穎反射式光子元件。根據實驗結果顯示，此元件具有可反轉旋性及可全波長做光子能隙的調控，而雷射輸出的調控於正常旋性下可達136 nm，於反旋性的情況下之雷射輸出調控可達190 nm。本論文首先量測此材料的基本特性，接著混入向列型液晶製成膽固醇液晶，並量測照光後光子能隙以及圓偏振性的可調控性。
本研究利用手性分子馬達作為膽固醇液晶的手性分子，藉由此手性材料照UV光會形成反旋性，以及提高溫度使提高回復初始旋性的效率，使兩者的反應速率達成動態平衡，藉此穩定反射波長。由實驗結果可知，先微調UV光照射膽固醇液晶樣品至光平穩狀態後，此時手性分子結構的變化過程為一動態平衡。若在此時改變照光強度或是改變環境溫度則改變此動態平衡下的光子能隙。因此藉由此調控方式，我們可於全波長作穩定調控。且在重複性的實驗中，在經過多次的循環下，其反射波段的位置並無明顯的差異。此外在雷射元件的應用中，我們將照光強度固定，然後微調溫度由25度至39度，可看到在此條件下，雷射輸出可由705 nm調控至569 nm，而所得的雷射閥值也介於13.63 ~18.99 nJ / pulse之間。

In this thesis, photo-responsive chiral molecular motors (CRs) with photo-invertible helix ability are doped with liquid crystals (LCs) to induce a tunable cholesteric LC (CLC). During the photo-isomerization of the CRs by UV irradiation, the photonic bandgap (PBG) of CLC can be tuned bidirectionally in the full visible region accompanying with the handedness reversal. In order to effectively manipulate this supramolecular system, we use the dynamic balance of two continuous light and thermal stimulation to establish stable conditions of control. The photo-stationary state can be obtained by the dynamic equilibrium between the concentrations of trans and cis enantiomers through simultaneous occurrence of photo inversion and thermal relaxation. Under this kinetically partial racemic homogeneous equilibrium condition, the PBG and circular polarization of the CLC can be accurately manipulated. Taking advantage of this unique property, we develop a reliable laser which has a broadband tunability and handedness invertibility.
The effective HTP is determined by the stereoselective photochemical equilibrium position of the chiral molecular motors composed of stable and unstable forms. Based on this advantage, a mirrorless bandedge laser with a broadband tunability and circular-polarization revertability can be obtained. The laser wavelength can be tuned more than 136 nm in stable trans state (initial handedness), and 190 nm in unstable cis state (inversed handedness).

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