Blue, surface-emitting, distributed feedback polyfluorene lasers

Abstract
We report the fabrication of optically-pumped solid-statedistributed feedback lasers utilizing two blue-light-emitting semiconducting polyfluorenes as gain media. The lasers were readily fabricated by solutiondeposition of thin polymer films on top of gratings etched into fused silica substrates. A compact Nd:YVO 4 microchip laser was used as the pump source for the two polymers studied, and lasing was achieved at 455 and 465 nm. Low threshold energies, ⩾4 nJ per pulse, were obtained. The emission characteristics of the lasers are described along with the results of additional experiments that investigate in more detail the effect of the gratingmicrostructure on polymer light emission.