Distributed feedback polymer laser with an external feedback structure fabricated by holographic polymerization technique

Distributed feedback polymer laser with a grating in the waveguide cladding layer was prepared by holographic polymer dispersed liquid crystals (HPDLCs). The holographic polymerization technique enables one-step formation of an organic grating on top of a homogenous semiconducting polymer poly(2-methoxy-5-(2′-ethyl-hexyloxy)-p-phenylenevinylene) (MEH-PPV) layer. Under optical pumping, a lasing threshold of 21 μJ/cm2 and a bandwidth of 0.7 nm were obtained in a single longitudinal mode operation. Further studies on the effect of the semiconducting polymer thickness show the amount of evanescent wave spread into the grating layer determines the laser performance of the proposed device.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► We use a one-step, low cost holographic polymerization technique to fabricate OSL. ► This novel OSL shows a performance of 2.7 × 103 W/cm2 lasing threshold. ► The external feedback structure allows precise control of structural parameters. ► The device performance is best when the active layer thickness is around 75 nm.