PURPOSE: To enable more efficient switching by providing the optical switch with a nonlinear optical medium having periodic polarity inversion structures in a part of at least either of two optical arms of a Mach-Zehnder interferometer.
CONSTITUTION: A signal light pulse 113 is made incident on the waveguide type interferometer 102 through a multiplexing mirror 109. The interferometer 102 is previously so set that an output is made zero for the input of only the signal light pulse 109 by applying the electric field to the second arm 104 of the interferometer 102 via an electrode 105 and finely adjusting the refractive index of the second arm 104 by an EO effect. A light control pulse 114 is then made incident on the interferometer 102 through the multiplexing mirror 109. The sum frequency generation process of the light control pulse 114 and the signal light pulse 113 takes place at the first arm 103 and the second arm 104 and the phase of the signal light pulse 109 changes in both arms. The zero output state of the interferometer 102 is broken by this phase transition and the signal light pulse 109 is outputted as an output light pulse 115.
YUBE MASAO
YOKOO ATSUSHI
ISHIBASHI SHIGEO
