Title :
Speed limit of all-optical gate switches using cascaded second-order nonlinear effect in quasi-phase-matched LiNbO3 devices
Author :
Fukuchi, Yutaka ; Sakamoto, Takahide ; Taira, Kenji ; Kikuchi, Kazuro ; Kunimatsu, Daisuke ; Suzuki, Akira ; Ito, Hiromasa
Author_Institution :
Res. Center for Adv. Sci. & Technol., Univ. of Tokyo, Japan
Abstract :
In all-optical gate switches that employ the cascaded second-order nonlinear effect in quasi-phase-matched (QPM) LiNbO/sub 3/ devices, walkoff between the fundamental and second harmonic pulses is very large. The authors experimentally show that crosstalk of the switch induced by such walkoff limits the switching speed, but that the switching speed can significantly be enhanced by walkoff compensation. Using a 20-mm-long QPM LiNbO/sub 3/ waveguide device, the authors switch one of twin pulses separated by 6.25 ps without crosstalk, showing the possibility of switching a 160-Gb/s signal.
Keywords :
lithium compounds; multiwave mixing; optical crosstalk; optical phase matching; optical switches; optical waveguides; 160 Gbit/s; 160-Gb/s signal switching; LiNbO/sub 3/; QPM LiNbO/sub 3/ waveguide device; all-optical gate switches; cascaded second-order nonlinear effect; crosstalk; four-wave mixing; fundamental pulses; periodically poled LiNbO/sub 3/; quasi-phase-matched LiNbO/sub 3/ devices; second harmonic pulses; speed limit; switching speed; walkoff compensation; Clocks; Fiber nonlinear optics; Nonlinear optics; Optical crosstalk; Optical harmonic generation; Optical mixing; Optical pumping; Optical switches; Optical wavelength conversion; Ultrafast optics;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2002.801074
