Patent ID: 7689081
Filing Date: 2010-03-30
Classification: G02F

Abstract:
1. An all-optical logic gate receiving amplitude-modulated first and second optical input signals, comprising: first and second optical input media receiving respective first and second optical input signals; a first combining medium optically coupled to the first and second optical input media to receive respective first and second optical input signals, the first combining medium generating a first combined signal based on the first and second optical input signals; third and fourth optical input media, the third optical input medium optically coupled to the optical output medium to receive the first combined signal as the third optical input signal, and the fourth optical input medium optically coupled to receive a fourth optical input signal having constant continuous wave (CW) light; a second combining medium optically coupled to the third and fourth optical input media to receive respective third and fourth optical input signals, the second combining medium generating a second combined signal based on the third and fourth optical input signals; and a first nonlinear element optically coupled to receive the second combined signal from the first combining medium and having an optical resonator with a resonant frequency tuned relative to the frequency of at least one of the first and second optical input signals so that the first nonlinear element generates a first optical output signal having a high logic level if both of the optical input signals have low logic levels, and generates the first optical output signal having a low logic level if either or both of the first and second signals has a high logic level, whereby the first nonlinear element performs NOR logic on the binary logic levels of the first and second optical input signals to generate the first optical output signal, the first optical output signal thus having a binary logic level that is amplitude-modulated; and at least one first optical output medium optically coupled to receive and output the first optical output signal generated by the first nonlinear element, wherein the first and second optical input media, the first combining medium, the first nonlinear element and the first optical output medium are formed in a photonic crystal, and wherein the first nonlinear element is optically positioned between an output of the first combining medium and an input to the first optical output medium so that nearly one-hundred percent of the power of the combined signal is output by the first nonlinear element as the first optical output signal if the NOR logic discrimination of the combined signal results in the first optical output signal having a high logic level.