Blue-light-emitting polymer lasers with non-periodic circular Bragg resonators

Organic copolymer lasing from single defect microcavity fabricated using laser patterning

“…We show that such defect structures generate lateral optical-confinement, increase cavity Q -factor and reduce lasing thresholds from 11 μJ cm −2 to 7 μJ cm −2 . This threshold is consistent with other reports using the same copolymer placed in a DFB, 40–42 (the lowest reported threshold being 1.2 μJ cm −2 ) and is lower than thresholds reported for other polymer DBR microcavities with similar structures (84 μJ cm −2 ). 31…”

“…40 Lasing from BN-PFO has been previously reported in DFBs, containing first and second order gratings, 41 together with non-periodic circular gratings. 42 In the work described here, we firstly investigate how the lasing performance of BN-PFO is affected by the relative concentration of the BN units and intermolecular packing. After having established which materials have the lowest gain thresholds, we then fabricate planar microcavity structures and use our recently developed laser patterning technique to write physical ‘defect’ structures inside the microcavity.…”