Spectroscopic and lasing properties of Er3+-doped glass microspheres

We report experimental results on the characterization of microspherical cavities fabricated in Er doped modified silica and phosphate glasses. The spectroscopic properties of the bulk precursor glasses as compared to the obtained microspheres were investigated by photoluminescence spectroscopy and lifetime measurement for the 4I13/2 4I15/2 transition of Er ions. In both types of glasses we demonstrate whispering gallery mode laser action at various wavelengths around 1550 nm by using a 1480 nm pump laser coupled through a tapered fiber.