Novel erbium complexes with low band-gap for infrared laser and optical amplifiers

Two new NIR luminescent erbium(Ill) crown-ethers have been synthesized and studied by optical spectroscopies. Both the complexes show absorption bands in the visible spectral region (absorption edge at about 500 nm and 600 nm) and exhibit the NIR lanthanide luminescence following excitation of the organic ligand. The absorption bands of these complexes, well in the visible region of the spectrum, make them ideal candidates as active molecules for efficient optically pumped laser and optical amplifier by excitation with commercially available lasers.