Flexible blue-emitting encapsulated organic semiconductor DFB laser

An organic laser based on a monodisperse star-shaped oligofluorene gain medium has been embodied in mechanically flexible format with distributed feedback templated from a holographic master grating. Laser emission was obtained from 425 to 442.5 nm with lowest soft pump threshold at 14.4 mu J/cm(2) (2.7 kW/cm(2)). We compare the performance of such lasers with and without encapsulation. Encapsulation enables stable operation in ambient atmosphere at a 1/e degradation energy dosage of 53 J/cm(2). (C) 2010 Optical Society of America