Multimode laser emission from BODIPY dye-doped polymer optical fiber

Abstract

We report the fabrication and investigations of lasing properties of dipyrromethene boron difluoride (BODIPY) dye-doped polymer optical fibers (DDPOFs) using two different pumping schemes. Here, we have explored BDIPA dye, a π-extended BODIPY derivative as the gain medium. A Q-switched Nd:YAG laser operating at 532 nm was used, as the pump source for the lasing studies. Stripe illumination using a cylindrical lens produces amplified spontaneous emission (ASE) in the fiber whereas a multimode laser emission at a low lasing threshold of 50 μJ was observed by spot illumination technique using a convex lens. The cylindrical surface of the optical fiber acts as a cavity and it provides the necessary optical feedback for the gain medium resulting in the observed lasing properties. The photostability of the fiber was investigated at higher pump energy of 2 mJ using a convex lens. Excellent results such as very low lasing threshold, high cavity Q-factor and photostability were observed for the fabricated BDIPA DDPOF, clearly indicating the use of the BDIPA dye as a prominent lasing material in solid-state dye lasers.