PURPOSE: To perform NOR operation with super high-speed by making plural incident lights incident on an optically nonlinear medium and detecting the presence or absence of a predetermined frequency component generated according to the combination of the plural incident lights.
CONSTITUTION: When input lights P1, P2 having optical frequencies f1, f2 are made incident on a semiconductor optical amplifier 1, i.e., the optically nonlinear medium, injected carrier by means of nearly degenerate our waves mixing are modulated by the beat frequency between frequencies f1, f2 and the replica frequency appears. When signal light PS having a frequency fS is made incident on the semiconductor optical amplifier 1, the signal light PS is modulated and the output light P'0 having a new frequency f'0 is generated so as to be outputted. By passing the intermediate output light P'0 through a narrow band optical filter 2 having a transmission frequency f0 the output light P0 having a frequency fSC is obtained. Consequently, by suitably setting the selection wavelength of the optical filter 2, an optical logical element for executing the desired logical operation with regard to the relation between the combination of the frequencies of incident lights P1, P2 and the output light P0.
SAKATA HARUHISA
MATSUSHIMA YUICHI
