Díaz-García, María A., Morales-Vidal, Marta, Villalvilla, José M., Boj, Pedro G., Quintana, José A., Retolaza, Aritz, Merino, Santos Label-free sensors based on perylenediimide-doped polystyrene distributed feedback lasers María A. Díaz-García ; Marta Morales-Vidal ; José M. Villalvilla ; Pedro G. Boj ; José A. Quintana ; Aritz Retolaza ; Santos Merino; Label-free sensors based on perylenediimide-doped polystyrene distributed feedback lasers. Proc. SPIE 9568, Organic Field-Effect Transistors XIV; and Organic Sensors and Bioelectronics VIII, 956823 (August 31, 2015); doi:10.1117/12.2187021 URI: http://hdl.handle.net/10045/60490 DOI: 10.1117/12.2187021 ISSN: 0277-786X ISBN: 9781628417340 Abstract: Distributed feedback (DFB) laser sensors with active films consisting of a highly efficient and photostable perylenediimide dye (perylene orange, PDI-O) dispersed in polysytrene (PS), used as passive matrix, are reported. PDIdoped- PS DFB lasers show an excellent operational durability under ambient conditions, superior to those of previously reported DFBs used for sensing purposes. Their bulk refractive index sensing capabilities, under exposure to liquids of different refractive index, have been determined from changes in their emission wavelength. The role of the active film thickness on both, the laser and the sensing performance, has been explored. The use of a thick active film (850 nm) allows obtaining the lowest possible threshold and highest operational lifetime for this type of device although the sensor sensitivity is lower than that achievable with a thin film (160 nm). It is also shown that the inclusion of a high refractive index TiO2 layer on top of the sensor structure allows improving the sensor sensitivity by around two times. Keywords:Sensors, Label-free, Organics, Lasers, Distributed feedback, Photostability SPIE, The International Society for Optics and Photonics info:eu-repo/semantics/article