Micromachining optical waveguides in bulk glass using a femtosecond laser oscillator

Summary form only given.We show that by focusing a femtosecond laser pulse very tightly, one can micromachine a transparent material using an unamplified laser. A 1.4 numerical aperture (NA) microscope objective is used to focus a 5 nJ, sub-100-fs pulse into a 0.5-/spl mu/m diameter spot inside a piece of Corning 0211 glass.