Ultrafast dynamics of intersystem crossing and resonance energy transfer in Er(III)-quinolinolate complexes

Organocomplexes with trivalent erbium are investigated by timeresolved optical spectroscopy techniques. Ultrafast time scales are reported for intraligand intersystem crossing (∼10 ps) and ligand-to-metal resonance energy transfer (∼100 ps), resulting in lanthanide-ion sensitization with nearly unity efficiency. Given the interest of erbium complexes for telecom wavelength solidstate amplifiers and emitters, the results should stimulate further theoretical investigations on radiationless transitions in such complexes.