Section 4. New lasers and electro-optic materials Spectroscopic and lasing properties of Er 3+ -doped glass microspheres

We report experimental results on the characterization of microspherical cavities fabricated in Er 3+ -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 4 I13/2 ! 4 I15/2 transition of Er 3+ 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.