Studies of the surface treatment effect for cholesteric blue phase liquid crystals lasers

• Main Authors: Yu-Han Kao, 高于涵
• Other Authors: Chi-Huang Lin
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/58835689059777196623

碩士 === 國立中山大學 === 物理學系研究所 === 100 === In this study, we study three kinds of surface treatments in the blue phase lasers. Three kinds of surface treatments include no surface treatment, homogeneous alignment ,HA, and vertical alignment ,VA. Blue Phase liquid crystal is a three-dimensional photonic crystal, and it can be used to be a laser cavity. When the blue phase doped with a laser dye, a laser emission can be observed under appropriate pumping energy. In the first part, we fabricate the blue phase lasers with three kinds of surface, there are different surface treatments to study the surface effect of the optoelectronic properties. It is found that the threshold pumping power is significantly decreased under a surface treatment on glass substrate. In the second part, we change cooling rate in the formation of the blue phase liquid crystals, and study the optoelectronic properties of blue phase lasers. The experiment results reveal that the slower cooling rate leads to a order blue phase substrate, resulting in a lower threshold pumping energy of the blue phase laser.