ABSTRACT

An all-solid organic semiconducting conjugated polymer poly(2-methoxy-5-(2ʹ-ethyl-hexyloxy)-p-phenylenevinylene) (MEH-PPV) activated polarisation grating (PG) laser was demonstrated for the first time. The PG structure was fabricated based on photoalignment and stacking of multiple reactive mesogen sublayers to provide distributed feedback, and the thin MEH-PPV layer on top acts as the gain medium covered by a protecting layer. Light generates in waveguide mode from the active layer and spreads into the PG structure by an evanescent wave to get stimulated amplification. Using MEH-PPV as the gain medium with high photoluminescence quantum yield and large cross-section for stimulated emission, low threshold PG lasing was obtained. The momentum conservation in the plane of waveguide allows lasing coupled into the free space at certain angle instead of from the sample edge. Therefore, the intrinsic polarisation of the laser emission can be preserved and the circularly polarised lasing property was demonstrated by the PG laser.

摘要

首次展示了一种全固态有机半导体共轭聚合物聚（2-甲氧基-5-（2′-乙基-己氧基）-对亚苯基亚乙烯基）（MEH-PPV）活化偏振光栅（PG）激光器。PG结构是基于光反应性和多个反应性液晶元亚层的堆叠以提供分布反馈而制造的，顶部的薄MEH-PPV层充当被保护层覆盖的增益介质。光从有源层以波导模式产生，并通过an逝波传播到PG结构中，从而得到受激放大。使用MEH-PPV作为具有高光致发光量子产率和大横截面的受激发射的增益介质，可以获得低阈值PG激光。波导平面中的动量守恒允许以一定角度而不是从样品边缘将激光耦合到自由空间中。因此，可以保持激光发射的固有偏振，并且通过PG激光器证明了圆偏振激光特性。