Wavelength division with three-dimensional couplers fabricated by filamentation of femtosecond laser pulses.
Refractive-index changes can be induced by filamentation of 800-nm, 1-kHz femtosecond laser pulses in silica glass. Two-dimensional translation of a 40-microm-long filament leads to the formation of a curved waveguide because of bending by the previously induced refractive-index change. The fabrication of 2-mm directional couplers to split the coupled beam into 1:1 at a wavelength of 632.8 nm is demonstrated. The realization of three-dimensional directional couplers and wavelength division in the output from the couplers is also demonstrated.
Watanabe
Wataru
W
Department of Material and Life Science, Graduate School of Engineering, Osaka University, 2-1, Yamadaoka, Suita, Osaka, 565-0871 Japan. watanabe@photonics.mls.eng.osaka-u.ac.jp
Asano
Taishi
T
Yamada
Kazuhiro
K
Itoh
Kazuyoshi
K
Nishii
Junji
J