Nanoimprinted polymer lasers with threshold below 100 W/cm2 using mixed-order distributed feedback resonators

Organic semiconductor lasers were fabricated by UVnanoimprint lithography with thresholds as low as 57 W/cm2 under 4 ns pulsed operation. The nanoimprinted lasers employed mixed-order distributed feedback resonators, with second-order gratings surrounded by first-order gratings, combined with a light-emitting conjugated polymer. They were pumped by InGaN LEDs to produce greenemitting lasers, with thresholds of 208 W/cm2 (102 nJ/pulse). These hybrid lasers incorporate a scalable UV-nanoimprint lithography process, compatible with high-performance LEDs, therefore we have demonstrated a coherent, compact, low-cost light source.