349 Laser Patterning of Functional Crystal Lines in Oxide Glasses

Thursday, November 5, 2009: 3:00 PM
Pancho Villa (Camino Real Hotel)
Takayuki Komatsu , Department of Materials Science and Technology, Nagaoka University of Technology, Nagaoka, Japan
Tsuyoshi Honma , Department of Materials Science and Technology, Nagaoka University of Technology, Nagaoka, Japan
Laser irradiation techniques for the patterning of functional crystal lines such as ferroelectric LiNbO3, ferroelastic β'-Gd2(MoO4)3, and lithium ion conductive LiFePO4 on the glass surface have been developed, i.e., rare-earth/transition metal atom heat processing methods, in which continuous wave lasers such as Yb:YVO4 (wavelength: 1064 nm) are irradiated onto glasses containing rare-earth (RE: Nd3+, Sm3+ etc) or transition metal (TM: Cu2+, Ni2+ etc) ions. The laser energy absorbed by RE or TM ions results in the local heating of the surrounding of RE or TM ions through the non-radiative relaxation process, consequently inducing the crystallization. By scanning laser at constant speeds such as 10 μm/s, nonlinear optical/ferroelectric crystal lines are patterned successfully on the glass surface. The high orientation of crystals in the lines is confirmed from the azimuthal dependence of second harmonic intensities and linearly polarized micro-Raman scattering spectra, i.e., the patterning of single crystal lines. It is also possible to pattern two-dimensional crystal bending or curved lines by just changing the laser scanning direction, and such bending crystal lines have a potential for optical waveguides.