Ultrafast Laser Processing of Glass

The emerging fabrication techniques for transparent materials such as glass and crystal that use focused ultra-short laser pulses will be reviewed from the viewpoint of functionalities of the products to be integrated into a future photonic system. The devices include waveguide and waveguide couplers, mirrors and lenses, filters and holograms. The future photonic system may consist of many functional subsystems which are connected through transparent gates or windows. Welding technique may play an important role for this system integration. The welding technique for transparent materials using ultra-short laser pulses will also be reviewed along with applications to hermetic sealing. The author presents experimental results on the temperature dynamics. The author will also discuss on an idea connecting the relaxation of internal stress and the high index change and a role of the void and its motion in the fabrication process. The bright near future and challenges of the glass processing techniques with ultrafast lasers will briefly be touched on.