Fabrication of three-dimensional photonic devices using femtosecond laser pulses

Abstract

Using tightly focused femtosecond laser pulses, we produced optical waveguide and devices in the transparent materials. This technique has the potential to generate not only channel waveguide but three-dimensional optical devices. In this paper, an optical splitter and U-grooves, which are used for fiber alignment, are simultaneously fabricated in a fused silica glass by using near-IR femtosecond laser pulses. The fiber aligned optical splitter has a low insertion loss, less than 4 dB, including intrinsic splitting loss of 3 dB and excess loss due to the passive alignment of a single-mode fiber. Finally, the utility of the femtosecond laser writing technique is demonstrated by fabricating gratings at the surface and inside the silica glass, respectively.