Pulsed laser interference patterning of polyimide grating for dye-doped polymer laser

作者：Kok Soon Yie; Tou Teck Yong; Yap Seong Ling; Yap Seong Shan

来源：Journal of Nanophotonics, 2016, 10(3): 033003.

DOI：10.1117/1.JNP.10.033003

• laser interference patterning
• thin film dye laser
• distributed feedback laser
• distributed Bragg reflector
• dye doped polymer laser
• polyimide

Direct laser interference patterning of polyimide (PI) films was performed by using a pulsed 355-nm laser. At laser fluence of 0.4 J/cm(2), gratings with spatial periods of 3.8 mu m to 344 nm were created. The highest aspect ratio of the grating structure (0.8) was obtained for the 344-nm grating. An all-polymer dye laser was then fabricated by spin-coating a layer of disodium fluorescein (DF)-doped polyvinyl alcohol (PVA) film on bare and patterned PI substrate. Green laser emission was obtained when transversely pumped by a 355-nm laser. The lasing threshold reduced by similar to 10 times for the sample with 344-nm grating while the laser intensity was similar to 18 times higher. The enhancements are ascribed to the 344-nm grating structures, which act as an efficient distributed feedback resonator and distributed Bragg reflector grating for DF-doped PVA emitting at similar to 563 nm, on top of being a passive light-trapping structures.

• 出版日期2016-7