Formation of void array inside transparent and absorptive glasses by femtosecond laser irradiation.
We demonstrate self-fabrication of void arrays in a fused silica transparent in the visible and a color-filter borosilicate glass strongly absorptive at 800 nm using tightly focused Ti-sapphire femtosecond laser pulses at 1 kHz without scanning. The period, the size, the number of voids, and the length of the aligned void structure were controlled by changing the laser pulse energy, and the position of the focal point inside two materials. The void arrays were observed by an optical microscope and also estimated by an optical diffraction experiment. The void size and period were smaller in the absorptive glass than in the transparent glass. The submicrometer-sized void was observed by a scanning electron microscope. The smaller and clearer void arrays were formed in the color filter than the fused silica glass. With increasing the laser focal depth, the void-array length increased in the fused silica and decreased in the color filter.
Department of Physics, Chungbuk National University, Cheongju 361-763, Korea.
Wooyoung
W
Jang
Daejin
D
Kim
Taehong
T
Kim
Ayoung
A
Moon
Ki-Soo
KS
Lim
Myeongkyu
M
Lee
Ik-Bu
IB
Sohn
D005898:Glass / Q000737:chemistry* / Q000528:radiation effects*; D007834:Lasers; D008422:Materials Testing; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects* / Q000648:ultrastructure*; D010316:Particle Size; D012031:Refractometry / Q000379:methods*