本論文將膽固醇液晶填充至具q-plate圓對稱式配向之液晶盒，並將雷射光束照射於樣品上方使雷射反射後獲得隨方位角變化之相位差，成功產生渦流光束。接續調製出兩種旋性的鐵電液晶摻混膽固醇液晶(FLC-CLC)複合智能材料填充入上述液晶盒內，此複合智能材料之Sm*-CLC相變點接近室溫，具備可高度調控光子能隙之特性，透過外加低值電壓以電致熱的方式使光子能隙調控範圍涵蓋全白光波段(400 nm~700 nm)，涵蓋範圍高達350 nm，大幅增加了此膽固醇液晶光渦流元件之可工作波長範圍。本實驗第一部分研究乃製作出Bragg-Berry光渦流產生元件(BBVG)，利用此元件產生渦流光束，並測量此光束及元件的特性，實驗發現此BBVG具備與膽固醇液晶相同的特性，若入射光並非垂直入射進樣品中，則此元件的反射頻譜會發生位移，此法可小幅調控元件的光子能隙。接著利用麥克森干涉法驗證平面波及球面波經過左旋與右旋的BBVG反射後產生的渦流光之拓樸荷符合理論值l=+2與-2，以及驗證干涉圖案確實會受到干涉光束之間的光程差所影響。第二部分乃致力於調配出可於室溫下調控且涵蓋全白光能隙的液晶材料，由於實驗中需生產兩種旋性的渦流光，因此材料有摻雜6 wt%鐵電型液晶之右旋FLC-CLC及摻雜4 wt%鐵電型液晶的左旋FLC-CLC，並將兩種材料灌回水平配向的ITO液晶盒內進行測試，於室溫T=22.5°C的情況下，右旋及左旋的FLC-CLC材料皆可於低電壓範圍下(≤3.2 V)調控並產生可全白光範圍調控的反射，且反射率與反射波帶皆無太大的衰減或變形。第三部分的研究中將FLC-CLC複合材料回灌入具有圓對稱配向的液晶盒中製成FLC-BBVG光渦流元件，並施加直流電壓調控其反射頻段於紅、綠與藍區，分別使用紅(632.8 nm)、綠(532 nm)及藍(442 nm)三原色的雷射光照射於此三波段之FLC-BBVG樣品上，使反射後的雷射光產生渦旋相位。最後，藉由麥克森干涉法的方式，驗證球面波及平面波產生的渦流光其拓樸荷l值符合理論預測。

In this thesis, an optical element called Bragg-Berry vortex generator (BBVG) was demonstrated based on ferroelectric liquid crystal and cholesteric liquid crystal (FLC-CLC) smart materials. The BBVG element was obtained by filling with the FLC-CLC materials into the indium-tin-oxide (ITO) glass cells which were pre-coated with a q-plate-like circularly-symmetric photoaligned pattern. After a non-vortex laser beam impinges into the BBVG, a reflective optical vortex beam with an azimuthal-angle(Φ)-dependent phase and thus an orbital angular momentum (OAM) will be obtained if the wavelength of the incident laser is included in the Bragg reflection band of the BBVG. To obtain optical vortex beams with oppositely-twisted phase structures (carrying with ±OAM), two BBVG elements with FLC-CLC mixtures of right- and left-handedness were prepared. The FLC-CLC smart materials can effectively reflect light within the reflection band or photonic bandgap (PBG) which can be easily tune with less sacrifices in reflectance and band shape throughout the full visible region by the application of a low DC voltage range (≤3.2 V) around room temperature. The oppositely-handed FLC-CLC BBVG elements can generate optical vortex beams with oppositely-handed OAM within the full visible region (400~700 nm) by simply tuning the PBG at specific voltages. Herein, the oppositely-handed BBVGs were demonstrated to generate oppositely-handed optical vortex beams with red (R), green (G), and blue (B) colors at different voltages if the incident laser beam has 632.8 nm, 442 nm, and 532 nm, respectively. The interferograms obtained experimentally based on Michelson interferometer were used to determine the OAM characteristics of the vortex beams including the topological charge number l and the twisting direction of the phase surface, which were consistent with the simulated results.

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