Logic gates based in two- and three-modes nonlinear optical fiber couplers

Abstract

In this paper we did a study of logic gates obtained in the operation of a three-core non linear directional coupler (TNLDC) and an asymmetric two-core coupler (DNLDC) operating in the CW regime (the laser signals have the same wavelength). The symmetric three-core coupler (TNLDC), with their cores identical, in a planar arrangement, was studied using a control pulse applied to the first core. The second structure is an asymmetric twocore coupler (DNLDC). Looking at the transmission characteristics of the device, through the direct and cross channel, we did a study of the extinction ratio (Xratio) of these devices. For both devices we did a numerical investigation with the objective to implement logic gates. The DNLDC supplied AND, OR and XOR gates while the TNLDC supplied AND, NAND, OR, XOR and NOT gates. In comparing the performance of both switches operating as logic gates (DNLDC and TNLDC) we define, for the first time, a figure-of-merit of the logic gates (FOMELG). In this criteria the FOMELG is defined as a function of the extinction ratio of the gate outputs. Comparing the same gates of the three and two-core NLDC we observe that the logical gates of the three-core TNLDC present a better performance than the one of the two-core DNLDC considering the figure of merit FOMELG, besides the fact that is simpler to fabricate a symmetrical coupler (with identical cores) comparing with an asymmetric coupler. We believe that the use of this figure of merit will be useful in the study of the performance of logic gates to be used in communication systems.

Numerical analysis in triangular and planar three-core nonlinear optical fiber couplers (TNLDC) operating logical gates

“…In tables 2a-2b three possibilities are leading for three different AND gates, in tables 3a-3b two possibilities and in table 1 one possibility. In comparing the logic gates, we will use the figure-of-merit of the logic gates [FOMELG(dB)] defined as a function of the extinction ratio of the gate outputs [3]. We will look for the sum of the module values of the extinction ratio [Xatio (dB)] for each output of the logic gate.…”

“…The performance was studied in view of the possible use of these devices as logic gates in optical networks. To compare the performance of these devices we will use a figure-of-merit of the logic gates (FOMELG) [3].…”

Explicit construction of single input–single output logic gates from three soliton solution of Manakov system

“…[14]. On the other hand, in fiber couplers a full set of logic functions including AND, NAND, XOR, NOT and OR gates are numerically demonstrated using two-core and three-core fiber coupler switches operating in the continuous wave regime [3]. Especially, it has been shown that the logic gates AND, OR and XOR can be constructed from an asymmetric two-core fiber coupler and in the symmetrical three core fiber coupler NAND, AND, OR, XOR and NOT logical gates can be realized.…”

All-optical AND, XOR, and NOT logic gates based on Y -branch photonic crystal waveguide

“…Recently, a number of schemes have been proposed to realize all-optical logic gates such as using dielectric (or metallic) waveguides, [3][4][5] nonlinear effects in optical fibers, [6][7] and semiconductor optical amplifiers. Recently, a number of schemes have been proposed to realize all-optical logic gates such as using dielectric (or metallic) waveguides, [3][4][5] nonlinear effects in optical fibers, [6][7] and semiconductor optical amplifiers.…”