Amplified spontaneous emission in polymer films doped with CdSe/CdS/ZnS colloidal quantum dots

Cd- and Pb-based colloidal quantum dots (QDs) and nanoplatelets are perspective materials for fabrication of active layers in photonic and plasmonic devices due to high values of optical gain (hundreds to 1200 cm⁻¹) under sufficient pump conditions [1, 2]. To obtain an optical gain, these nanocrystals are usually deposited densely and close-packed. Several drawbacks like scattering and difficulties associated with fabrication of such layers limit their use. We report successful aggregate free doping of polymer layers with homogeneously dispersed CdSe/CdS/ZnS QDs and provide description of two compositions that can accommodate up to 30-50 mass. % of QDs. The compositions can be polymerized with usual acrylate photoinitiation process or via thiol-ene polymerization process. QDs are well dispersed before and after heat- and photopolymerization, form no aggregates and, thus, the formed layers are almost free from scattering losses. Amplified spontaneous emission (ASE) in QD doped polymers was observed with 532 nm wavelength laser excitation in the variable stripe length (VSL) configuration. (paper)