Effect of luminescent nanocrystal alignment on fluorescence anisotropy and light guiding in polymer films

Abstract

Elongated semiconductor nanocrystals with oriented transition dipoles, such as nanorods (NRs) and elongated nanoplatelets (NPLs), can exhibit emission anisotropy when confined in thin films. In this work, we report the effect of nanocrystal alignment on thin polymer film optical properties including absorbance, fluorescence polarisation and light guiding. We find that changes in absorbance after stretching films containing elongated nanocrystals are associated with changes in nanocrystal alignment. Stretching the NPL films induces fluorescence anisotropy, which follows an exponential trend that can be approximated as linear within a moderate range of true strain values. This empirical relati..