Near-infrared luminescent polymer waveguide with a 20 dB small-signal gain

摘要

Near-infrared optical gain in luminescent polymeric slab asymmetric waveguides has been investigated by use of amplified spontaneous emission. Upon nanosecond photopumping, the waveguides have shown a small-signal gain coefficient of 37.2 ±2.1 cm~(-1) at 820 nm for a pump fluence of 1.57 mJ/cm~2 (314 kW/cm~2). The loss coefficient and transparency fluence have been found to be 7.3 ± 1.0 cm~(-1) at 820 nm and 0.14 mJ/cm~2 (28 kW/cm~2), respectively. Furthermore, we show that a small-signal gain of 19.7 ±2.3 dB is achievable in a 1.2-mm-long waveguide.