Persistent spectral hole burning of Eu (III) complex dispersed silica composite materials prepared by sol–gel method

Europium (III) complex [Eu(15-crown-5)]Cl3, was doped into SiO2 matrices derived from tetraethyl orthosilicate (TEOS) by the sol–gel method. The properties of persistent spectral hole burning (PSHB) were characterized by the burning temperature and the temperature cycling experiment. For SiO2 : [Eu(15-crown-5)]3+, the spectral holes were burned at the temperatures between 10 and 300 K. In comparison with SiO2 : Eu3+, the formation efficiency of the holes was enhanced by the complexation of Eu3+ ions with crown ether ligands. The hole formation mechanism was discussed on the basis of quantitative analysis of the PSHB characters.