Rare-earth doped photonic crystal microcavities prepared by sol–gel

Rare-earth doped photonic materials and structures have been prepared by sol–gel processing, in the form of 1D photonic bandgap multilayer stacks of silica and titania. A significant enhancement of the Er3+ emission at ca. 1530 nm occurred when these ions were inserted into Bragg mirrors and microcavities. In Er3+/Yb3+ co-doped structures, an efficient energy transfer at 980 nm was observed from Yb3+ to Er3+ when these ions were in close proximity and especially when they were simultaneously present, in the same defect layer, with a 1530 nm photoluminescence enhancement of up to ∼25 times being observed for excitation at 980 nm, compared to the excitation of the same microcavities samples at 514.5 nm.