本篇論文主要是探討摻雜雷射的膽固醇液晶雷射元件，在這個實驗中我們發現膽固醇液晶雷射元件不只在正向有雷射輸出在cone角上也有雷射的輸出形式。我們也發現cone角雷射和膽固醇液晶的反射頻譜隨著角度的增大有往短波長移動的趨勢，而在約35度的時候有一圈特別強的光環產生。利用此機制，我們可以利用不同液晶和親手性分子比重來調配不同的膽固醇反射波段，藉以摻雜雷射雷料來達到不同顏色的雷射。我們也將模擬各個角度band edge的群速是趨近於零導致DOS變多，並測量不同角度出來的雷射是否和正向出來的雷射擁有相同的偏振。最後利用這個雷射元件我們將做出一個相當具有價值的角度調變雷射輸出波長元件。

This investigation reports an anomalous wide-banded color cone lasing (WBCCL) emission based on a planar dye-doped cholesteric liquid crystal (DDCLC) film with a single pitch. The lasing wavelength (las) in the WBCCL emission distributes continuously from 676.7 to 595.6 nm (~80nm band) measured at continuously increasing oblique angle relative to the helical axis from 0o to 50o. It is demonstrated that the lasing wavelength is exactly coincided with the wavelength at the long wavelength edge (LWE) of the CLC reflection band (CLCRB) at each oblique angle, that is, the low-threshold edge lasing can occur not only at normal direction but also at oblique direction. The stimulated result of the dispersion relation at different oblique angles using Berreman’s 44 matrix method fit in well with the experimental results. Besides, the inhomogeneous distribution of the intensity of the WBCCL emission is attributed to two factors: the loss of the fluorescence from the multi-reflection and the fluorescence spectrum from the spontaneous emission of the dyes. A particularly bright lasing ring occurred at 35o can be explained qualitatively to be due to the double amplification of fluorescence under the overlap between the LWE of the CLCRB at 35o and the SWE of the CLCRB at 0o. Color cone lasing band can be tuned by changing the pitch of the DDCLC cell.

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