Improved operational lifetime of semiconducting polymer lasers by encapsulation

We report polymer distributed feedback lasers with dramatically extended operational lifetimes by using a simple encapsulation process. The lasers are configured as surface emitting, two-dimensional distributed feedback lasers based on the polymer poly[2-methoxy-5-(2(')-ethylhexyloxy)-1,4-phenylene vinylene]. The microstructure is transferred to the polymer surface through solvent assisted micromolding. Once encapsulated, a 2500-fold improvement in lifetime is demonstrated under ambient conditions, compared to the unencapsulated device. A blueshift of the emission wavelength observed during operation is characterized by absorption and ellipsometry measurements and attributed to a change in effective index due to a loss of conjugation in the polymer. (c) 2007 American Institute of Physics.