Multi-wavelength excited triplet–triplet upconversion microcrystals based on hot-band excitation for optical information encryption

Abstract

Multi-wavelength hot-band excitation, forbidden in the conventional Stokes fluorescence mechanism, is found to be available when cascading triplet-triplet annihilation upconversion (TTA-UC). Selective excitation of Pt(II)octaethylporphyrin (PtOEP) by diode laser with...