介绍了一种基于聚二甲基硅氧烷(PDMS)基片的回音壁模式(WGM)光纤激光器。激光器主要由多模石英光纤、塑料楔形光纤、激光染料溶液、玻璃基底和PDMS基片构成。将一根直径为279μm的石英裸光纤和一根直径为200μm的塑料楔形光纤耦合后固定在一块长和宽分别为2cm和1cm的玻璃基底上,在玻璃基底上浇注PDMS溶液后再经烘干形成厚度约为400μm的柔性PDMS基片。在基片上石英光纤与楔形光纤的耦合位置处刻出一个长为0.4cm,宽和高均为400μm的光纤沟道,在沟道中填人诺丹明6G的乙醇溶液并用另外一块玻璃基片封装后构成基于PDMS基片的回音壁模式光纤激光器芯片。采用沿石英光纤轴向消逝波光抽运方式,在PDMS芯片上实现了抽运能量为8.5μJ的低阈值的回音壁模式激光定向输出。
A whispering-gallery-mode (WGM) fiber laser integrated on a polydimethylsiloxane (PDMS) chip is presented which consists of a multimode quartz optical fiber, plastic wedge optical fiber, lasing dye solution, a glass and a PDMS substrate. A multimode quartz unclad optical fiber with a diameter of 279 μm and a plastic wedge optical fiber with a diameter of 200 μm are coupled and fixed on a glass substrate, and the length and width of the glass substrate are 2 cm and 1 cm, respectively. By pouring liquid PDMS on the glass substrate and oven dry, a flexible PDMS substrate (thickness is about 400 μm) is shaped. Then a fiber channel (length is 0.4 cm, both width and height are 400 μm) is carved in the contact position between PDMS and the coupled optical fiber. Mter injecting ethanol solutions of rhodamine 6G into the channel and packaging by a cover glass, a WGM laser chip integrated on a PDMS substrate is fabricated. Pumped by evanescent wave along the quartz optical fiber axis, low threshold energy of 8.5 μJ and directional WGM lasing emission has been successfully achieved on a PDMS chip.