Appl. Phys. Lett. 102, 073101 (2013)

Research into dye-doped polymer lasers is popular because of the ease with which dyes can be incorporated into polymers and the broad range of emission wavelengths that can be obtained by using different dyes. Vincent Reboud and co-workers from Spain, France, Poland and Ireland now report how single-step nanoimprint lithography can be used to fabricate polymer lasers on two-dimensional photonic-crystal slabs. They believe this approach will be more cost-effective than existing fabrication techniques because of its ability to pattern large volumes of polymer with a high resolution in a single step. The team used their process to make nanoimprinted triangular-lattice photonic crystals in a dye-chromophore-loaded printable polymer. Using optical pumping with a 532-nm frequency-doubled Q-switched Nd:VO4 laser emitting 1-ns pulses at 10 Hz, the team observed lasing at the photonic bandedge at thresholds as low as 3 μJ mm−2. The lasing threshold was found to depend on the dye concentration and the lattice constant of the photonic crystals. The findings demonstrate the suitability of nanoimprint lithography to produce cost-effective optically pumped lasers. The researchers suggest that the laser lifetime could be increased by replacing the dye molecules with optically active semiconductor nanocrystals.