Flexible blue-emitting encapsulated organic semiconductor DFB laser.

Mechanically flexible distributed feedback (DFB) lasers are fabricated by a low-cost approach using soft-lithography from a holographic master grating. The gain material is a star-shaped oligofluorene providing laser emission from 425 to 442 nm with a soft pump threshold at 14.4 µJ/cm (2.7 kW/cm). Encapsulation of the devices enables stable operation in ambient atmosphere at a 1/e degradation energy dosage of 53 J/cm.