All-optical or logic gate based on a photonic crystal fiber Michelson interferometer operating with pulse-position modulation

Abstract

We present a numerical investigation of the study of the Michelson interferometer by exploring the potential of such a device to act as an all-optical logic gate when excited with ultrashort pulses of 100 fs. The input pulse is controlled by a pulse-position modulation (PPM) modulator, which has the role of controlling the value and direction of the temporal displacement from the variation of the PPM modulating factor. We present the study on the signal-to-noise ratio (SNR), which served as the basis for constructing a merit figure of the studied logic gates in order to verify their performance. We considered pulse propagation under the influence of dispersive effects, as well as the nonlinear effects in the propagation regime with no loss for the input pulses. It was possible to implement the OR logic operation in at least one interval of the modulation adjustment parameter in each of the distinct pumping power regimes, thus obtaining a total of nine intervals of OR logic gate. The situation with the best SNR = 29.36 dB, for the suggested logic gate operation, was found at the power of 150 kW with the modulation adjustment parameter e = 43 fs. Numerical studies were done from the coupled–coupled equations solved using the fourth-order Runge–Kutta method. The implementation of fully optical logic gates tends to revolutionize digital systems in the field of data storage, such as optical memory, “replacement” of electronic circuits among other applications.