中国物理B ›› 2016, Vol. 25 ›› Issue (9): 94209-094209.doi: 10.1088/1674-1056/25/9/094209
• SPECIAL TOPIC—Physical research in liquid crystal • 上一篇 下一篇
Random lasing in dye-doped polymer dispersed liquid crystal film
Rina Wu(乌日娜), Rui-xin Shi(史瑞新), Xiaojiao Wu(邬小娇), Jie Wu(吴杰), Qin Dai(岱钦)
- 1. School of Science, Shenyang Ligong University, Shenyang 110159, China;
2. School and Hospital of Stomatology, Jilin University, Changchun 130021, China
Random lasing in dye-doped polymer dispersed liquid crystal film
Rina Wu(乌日娜)1, Rui-xin Shi(史瑞新)2, Xiaojiao Wu(邬小娇)1, Jie Wu(吴杰)1, Qin Dai(岱钦)1
- 1. School of Science, Shenyang Ligong University, Shenyang 110159, China;
2. School and Hospital of Stomatology, Jilin University, Changchun 130021, China
摘要： A dye-doped polymer-dispersed liquid crystal film was designed and fabricated, and random lasing action was studied. A mixture of laser dye, nematic liquid crystal, chiral dopant, and PVA was used to prepare the dye-doped polymer-dispersed liquid crystal film by means of microcapsules. Scanning electron microscopy analysis showed that most liquid crystal droplets in the polymer matrix ranged from 30 μm to 40 μm, the size of the liquid crystal droplets was small. Under frequency doubled 532 nm Nd:YAG laser-pumped optical excitation, a plurality of discrete and sharp random laser radiation peaks could be measured in the range of 575-590 nm. The line-width of the lasing peak was 0.2 nm and the threshold of the random lasing was 9 mJ. Under heating, the emission peaks of random lasing disappeared. By detecting the emission light spot energy distribution, the mechanism of radiation was found to be random lasing. The random lasing radiation mechanism was then analyzed and discussed. Experimental results indicated that the size of the liquid crystal droplets is the decisive factor that influences the lasing mechanism. The surface anchor role can be ignored when the size of the liquid crystal droplets in the polymer matrix is small, which is beneficial to form multiple scattering. The transmission path of photons is similar to that in a ring cavity, providing feedback to obtain random lasing output.
中图分类号: (Dye lasers)
- 42.55.Mv