Tunable distributed feedback lasing with low threshold and high slope efficiency from electroluminescent conjugated polymer waveguide

We present here tunable lasing from holographic distributed feedback (DFB) resonator of electroluminescent conjugated polymer waveguide. Tunable holographic lasing from 560 to 590 nm was simply achieved by rotating a Lloyd-mirror waveguide configuration. Lasing performance for the first order (m = 1) is superior to that for the second order (m = 2). Threshold for lasing for m = 1 is in the range of 25 to 50 μJ/cm²/pulse, which is close to that for amplified spontaneous emission (ASE), and that for m = 2 is larger than 104 μJ/cm²/pulse. For m = 1, slope efficiency of 7.3% including ASE in addition to lasing emission was measured, whereas for m = 2 slope efficiency between 0.1 and 0.2% was measured.