Emission properties of femtosecond (fs) laser fabricated microstructures in Polystyrene (PS)

Femtosecond-laser direct writing in polymers and potential applications in microfluidics and memory devices

“…This bond scission leads to formation of different optical centers and defects. [8][9][10][11][12][13][14][17][18] Interestingly, we observed similar emission in mechanically scratched/disturbed polymers. Some of these results were reported earlier by our group.…”

“…We observed structure-width increasing with the energy, number of scans, scan speed and focusing. [8][9][10][11][12][13][14] By increasing energy and number of scans, the irradiated region was exposed to a higher irradiation dose, which resulted in increased structure width. By reducing the scan speed also, one would expect similar results as the region was exposed to more irradiation.…”

“…Some of these results were reported earlier by our group. [8][9][10][11][12][13][14] This opened doors for the use of fs-irradiated polymers for memory-based devices. One can fabricate microcraters on the surface of a polymer using an fs-laser direct writing technique.…”

Direct Writing in Polymers with Femtosecond Laser Pulses: Physics and Applications

“…We could clearly observe pseudo-green color from the fs laser modified regions which is an indication of emission. Similar results were obtained in case of other polymers also, details of which are summarized in references [35][36][37][38][39][40][41]. By combining the formation of micro-craters (which took place at high scan speed >3 mm/s and low energies of ~nJ) and the emission coming from the modified regions we establish the possibility of using the fluorescent micro-craters towards memory based applications.…”

Femtosecond Laser Direct Writing and Spectroscopic Characterization of Microstructures, Craters, and Gratings in Bulk∕Thin Films of Polystyrene

“…We have fabricated such several structures in other polymers such as PMMA, PDMS, and PVA. In all these polymers we observed the formation of free radicals that exhibit emission upon fs laser irradiation and paramagnetic behavior (except for PVA) [10][11][12][13][14].…”