Fabrication by rf-sputtering and assessment of dielectric Er3+ doped monolithic 1-D microcavity for coherent emission at 1.5 um

All Er³⁺ doped dielectric 1-D microcavity are fabricated by RF sputtering technique. The microcavity is composed of half wave Er³⁺ doped SiO₂ active layer inserted, between two Bragg reflectors consisting of seven pairs of SiO₂/TiO₂ layers also doped with Er³⁺ ions. The morphology of the structure is inspected with scanning electron microscopy. Transmission measurements show the third and first order cavity resonance at 530 nm and 1535 nm, respectively. The photoluminescence measurements were obtained by optically exciting at the third order cavity resonance using 514.5 nm Ar⁺ laser with an excitation angle of 30°. The Full Width at Half Maximum of the emission peak at 1535 nm decrease with the pump power until the spectral resolution of the detection system of 2.3 nm. Moreover, the emission intensity presents a non-linear behavior with the pump power and a threshold at about 4 μW.