Manfredi G, Lova P, Di Stasio F, Rastogi P, Krahne R, Comoretto D
Dipartimento di Chimica e Chimica Industriale, Università Degli Studi di Genova Genoa Italy
Nanochemistry Department, Istituto Italiano di Tecnologia Genoa Italy.
RSC Adv. 2018 Apr 9;8(23):13026-13033. doi: 10.1039/c8ra01282b. eCollection 2018 Apr 3.
Colloidal nanocrystals attract considerable attention in the field of light emitting devices thanks to their high fluorescence quantum yield, low amplified spontaneous emission (ASE) threshold, and spectral tunability electronic structure engineering and surface functionalization. Combining polymer microcavities with colloidal nanocrystals as gain material promises a solution-based fabrication route to plastic laser cavities as well as applications in the field of smart flexible large area light sources and sensors. Here we demonstrate lasing from polymer microcavities embedding solution processable dot-in-rod (DiR) CdSe/CdS nanocrystals. Two highly reflective polymer dielectric mirrors are prepared by spin-coating of alternated layers of polyacrylic acid and poly(-vinyl carbazole), with their photonic band gap tailored to the emission of the DiRs. The DiRs are enclosed in the polymer microcavity by drop-cast deposition on one mirror, followed by pressing the mirrors onto each other. We obtain excellent overlap of the ASE band of the DiRs with the photonic band gap of the cavity and observe optically pumped lasing at 640 nm with a threshold of about 50 μJ cm.
由于具有高荧光量子产率、低放大自发辐射（ASE）阈值以及通过电子结构工程和表面功能化实现的光谱可调性，胶体纳米晶体在发光器件领域引起了广泛关注。将聚合物微腔与胶体纳米晶体作为增益材料相结合，有望为塑料激光腔提供一种基于溶液的制造途径，并应用于智能柔性大面积光源和传感器领域。在此，我们展示了嵌入可溶液加工的棒中 dots（DiR）CdSe/CdS 纳米晶体的聚合物微腔的激光发射。通过旋涂聚丙烯酸和聚（乙烯基咔唑）的交替层制备了两个高反射聚合物介电镜，其光子带隙针对 DiR 的发射进行了调整。通过将 DiR 滴铸沉积在一个镜面上，然后将两个镜面相互挤压，将 DiR 封装在聚合物微腔中。我们获得了 DiR 的 ASE 带与腔的光子带隙的出色重叠，并观察到在 640 nm 处的光泵浦激光发射，阈值约为 50 μJ/cm²。
