Devendra Chack

All-Optical XOR Gate Based on XGM Properties of SOA

A new configuration of all-optical 2 input XOR Gate is proposed that incorporates two semiconductor optical amplifiers (SOAs). The proposed XOR Logic is numerically simulated by solving nonlinear coupled equations that explain cross gain modulation (XGM) effect in individual SOAs. In this paper we describe a novel all-optical binary all-optical 2 input XOR Gate that demonstrates the ability of all-optical digital processing to perform even more complex operations.

Design and performance analysis of InP/InGaAsP-MMI based 1310/1550-nm wavelength division demultiplexer with tapered waveguide geometry

Abstract The design and performance analysis of a 1310/1550-nm wavelength division demultiplexer with tapered geometry based on InP/InGaAsP multimode interference (MMI) coupler has been carried out. Wavelength response of demultiplexer of conventional MMI and tapered input and tapered output (tapered I/O) waveguides geometry of the MMI have been discussed. The demultiplexing function has been first performed by choosing a suitable refractive index of the guiding region and geometrical parameters such as the width and length of MMI structure have been achieved. Access width of tapered I/O waveguides have been adjusted to give a low insertion loss (IL) and high extinction ratio (ER) for the considered wavelengths of 1310 nm and 1550 nm. The total size of the demultiplexer has been significantly reduced over the existing MMI devices. Numerical simulations with finite difference beam propagation method are applied to design and optimize the operation of the proposed demultiplexer.

Analysis of Step Discontinuity in a Single Mode Planar Slab Taper Optical Waveguide

In this paper we study the thin taper optical wave guide structure by using the step discontinuity model. The technique presented is unique and not being discussed elsewhere. We study the power loss and effect on mode field pattern due to step discontinuity for the case of symmetric single mode planar taper wave guide structure. The only assumption, we consider is that there are no reflection of fields at the step discontinuity point. In this paper we also assume that there are no mode conversions due to discontinuity effect and the structure maintain the single mode operation even at the step discontinuity point. We deliberately considered the thin taper structure to be valid on single mode operation. The technique presented can be easily extended to more complicated wave guide structure like asymmetric wave guide structure, ridge wave guide structure etc.

Propagation Study of Y-Junction Optical Splitter Using BPM

In this paper we have established the fundamental concept of guided wave for Y-branch suffer from power loss, due branching angle. Beam propagation methods are used to obtain guided wave characteristics, includes power loss between different branching angles. Guided light suffers loss owing to the tapered and separating structure. All simulations are done using opti BPM software. The power loss due branching angle is predicted. The results presented, have an application in DWDM optical networks.

2- Input AND Gate For Fast Gating and Switching Based On XGM Properties of InGaAsP Semiconductor Optical Amplifier

We report on an all-optical AND-gate using simultaneous Four-Wave Mixing (FWM) and Cross-Gain Modulation (XGM) in a semiconductor optical amplifier (SOA). The operation of the proposed AND gate is simulated and the results demonstrate its effectiveness. This AND gate could provide a new possibility for all-optical computing and all-optical routing in future all-optical networks. In an AND ( AB ) gate, Boolean is firstly obtained by using signal B as a pump beam and clock signal as a probe beam in SOA-1. By passing signal A as a probe beam and as a pump beam through SOA-2, Boolean AB is acquired. Proposed optical logic unit is based on coupled nonlinear equations describing XGM and FWM effects. These equations are first solved to generate the pump, probe and conjugate pulses in a SOA. The pulse behavior are analyzed and applied to realize behavior of all-optical AND gate and its function is verified with the help of waveform and analytical assumption.

Performance analysis of 1310/1490 Nm demultiplexer based on multimode interference coupler for PON

The design and analysis of a 1310/1490-nm demultiplexer based on Multimode Interference (MMI) coupler for Passive Optical Networks (PON) has been studied in this paper. Numerical simulations with finite difference Beam Propagation Method (BPM) have been utilized to optimize the operation of the proposed demultiplexer. The device has been designed with optimized width and MMI length and its analysis has been done based on extinction ratio and Insertion loss. Restricted interference has been used to reduce the size of the device. The device has been solely designed using 1310 nm as upstream and 1490 nm as downstream of data for Passive Optical Network communication system.

Analyzing the Optimum Parameter of an 1x2 MMI Splitter

Here we have optimized the branching separation distance of Multimode interference splitter to overcome the power loss. We search the critical parameters like length and width of Multimode interference splitter and the branching separation between two output ports which give the maximum output field for the desired Wavelength. We also had seen the performance of given structure at different wavelength in which the third window gives highest field of propagation. Simulation is based on the method of finite difference beam propagation method.