Plane Wave Expansion Technique Research Articles

Frequency encoded tristate Pauli X-gate using SOA assisted photonic band gap crystal

The quantum optical tristate Pauli-X gate can broadly be used due to its very fast speed of operation up to THz order, very fast information processing rate, and a wide domain of application. This Pauli X-gate is also important as it can undergo inversion operation. In this proposed scheme, the quantum tristate Pauli-X logic gate has been constructed by a closely packed square lattice of 2D air photonic band gap crystal (PhCs) composed of GaAsInP-dopped rods. The photonic band gap crystal-based tristate Pauli-X gate is performed also as an all-optical reversible quantum logic gate which has the character of low-powered output, very fast speed and a densely packed design structure. This photonic crystal-based structure is also verified by simulation experiment that this proposed scheme performs as the path of two input signals are cross-exchanged to one another at the output, retaining the path of the other input signal same. In this paper, the frequency encoding technique is used in all the designs to establish the logic of all-optical tristate Pauli X-gate towards the need of obtaining a three-input-three-output inversion system. The frequency encoding technique and the photonic crystal-based three Semiconductor Optical Amplifiers (pc-SOAs) are used here in all the schemes to establish the logic of the tristate Pauli-X gate scheme. Tristate Pauli-X gates have been designed and analyzed by Finite-Difference Time-Domain (FDTD) and Plane Wave Expansion (PWE) techniques. The Plane Wave Expansion (PWE) technique is used here in each system for determining the frequency range of band gap structure of transverse electric (TE) mode in the units of μm-1. All of these devices perform within the frequency range 0.629818≤ω2πc≤0.888037 and 1.17551≤ω2πc ≤ 1.34921 μm-1. The wafer dimension of each photonic band gap crystal-based device is 19.20 μm (length) × 16.20 μm (width) providing a very fast response time and very fast information handling (bit rate) capacity, which is found good for these THz Photonic crystal devices. Simulation results show that the proposed gate provides a response period of 0.291 ps and a bit rate of 3.44 Tbps, operating with a low input power of 3.45 mW. The reversible gate exhibits a response period of 0.289 ps and a bit rate of 3.46 Tbps, operating also with a low input power of 2.70 mW. Additionally, the alternative Pauli-X gate demonstrates a response time of 0.291 ps and a bit rate of 3.44 Tbps, operating with a low input power of 2.83 mW.

A 2D GaAs-Based Photonic Crystal Biosensor for Malaria Detection

Gallium arsenide (GaAs) composite semi-conductive rods with an air background lattice act as the building blocks for the photonic crystal structure used of a biosensor. The study presents a biosensor of a two-rod nano-cavity for identifying distinct stages of plasmodium falciparum in red blood cells (RBCs) in the early detection of malaria. The proposed biosensor enables the creation of a label-free biosensing environment in which optical and dispersion properties are investigated using plane wave expansion (PWE) and finite-difference time-domain (FDTD) techniques. The biosensor, with a sensing region for an analyte, is utilized to detect a change in refractive index to differentiate between normal RBCs and plasmodium falciparum-infected cells. The results show that the biosensor has a high sensitivity of 798.143 nm/RIU, a high Q-factor of 9881.926, a low detection limit (δ) of 222.4 × 10-6 RIU, a high FOM of 4496.079 RIU-1, and a compact area of 46.14 µm2.

Ultra-fast all-optical 8-to-3 encoder utilizing photonic crystal fiber

This work proposes a novel design of an 8-to-3 encoder in a photonic crystal fiber (PCF). It is composed of a buffer and three OR logic gates using circular air holes in a silicon dioxide substrate. We have employed the plane-wave expansion technique to analyze the band structure of the proposed PCF and the beam propagation method to study the transmission efficiency and electromagnetic field distributions. Our findings reveal that the encoder operates well within the main third telecommunication window, which corresponds to 1530–1565 nm. The numerical calculations show that transmissions greater than 70% and less than 0.05% are logics 1 and 0, respectively. The proposed encoder has a maximum delay of 7.5 ps, and its total footprint is about 140 µm × 14 µm × 3 mm. This makes the proposed PCF-based encoder suitable for simple and low-cost fabrication, which may find applications in optical communication devices and integrated circuits.

Ultra-fast tunable optoelectronic full-adder based on photonic crystal ring resonators covered by graphene nanoshells

This paper reports a novel design of a tunable optoelectronic full-adder using two photonic crystal ring resonators (PCRRs). Every PCRR consists of a matrix of silicon rods surrounded by silica rods coated with graphene nanoshells (GNSs). The proposed full-adder is formed by three input ports, two PCRRs, and two output ports for ‘SUM’ and ‘CARRY’. The plane wave expansion technique is used to study the photonic band structure of the fundamental photonic crystal (PhC) microstructure, and the finite-difference time-domain method is also employed in the final design for solving Maxwell's equations to analyze the light propagation inside the structure. We can tune the PhC resonant mode for our desired application by setting the chemical potential of GNSs with an appropriate gate voltage. The numerical results reveal that when the chemical potential of GNSs changes, the switching mechanism occurs and manages the coupling and propagation direction of the input beam inside the structure. We systematically study the effects of physical parameters on the transmission, reflection, and absorption spectra . Our numerical results also demonstrate that the maximum delay is about 0.8 ps. The 663 μm 2 area of the proposed full-adder based on two-dimensional materials makes it a building block of every photonic integrated circuit used for data processing systems. • A fast and compact all-optical full-adder using photonic crystal ring resonators (PCRRs). • A maximum steady-state time of about 0.8 ps and the structure's total size of 663 μm 2 . • There is no need to increase the input intensity for the appearance of the nonlinear effect. • The ON-OFF contrast ratios for Sum and Carry are 16 dB and 14 dB, respectively. • The full-adder is applicable in optical integrated circuits for high-speed signal processing.

A proposal of 3D sensor for rapid detection of breast tumour cell using photonic structure

The present research proposes a method that can identify tumour cells present in the human breast with the help of a plasmon-based three-dimensional (3D) photonic structure. The mechanism of detection of cells (tumour or normal) is realised through the analysis of the photonic bandgap of the proposed copper-based plasmonic structure. Moreover, the plane-wave expansion technique is applied to find the solution of the Helmholtz equation that determines the band structure. In this process, three signals with frequencies of 0.5, 1.0 and 1.5 THz are allowed to impinge on the structure to obtain the required results. The detection of cells that may be normal or suffering from tumour is confirmed by the reflected signal from the 3D photonic structure. More precisely, the bandgap analysis suggests that the cell is cancerous (suffering from tumour) if the reflected signal falls within the blue regime. In contrast, if the signal received finds a place within the violet regime of the spectrum, then this is an indication of a normal cell.

Realization of 3D reflectors by using metal-air and semiconductor-air based photonic structures at three communication windows

This study is based on analysis of 3D photonic crystal structure (PCS) for realization of photonic reflector pertaining to suitable optical communication wavelengths of 850, 1310 and 1550 nm. The said photonic reflector application is envisaged separately by two 3D PCSs, which comprise semiconductor (germanium) and metal (iron) based circular rods respectively, arranged on a square lattice having air as the background material. The plane wave expansion (PWE) technique is employed to investigate the photonic band gap (PBG) vis-à-vis all the aforementioned wavelengths. PBG is meticulously controlled by suitably selected various structure parameters, such as lattice spacing, diameter of the circular rods and nature of their material. Simulation outcomes explored that semiconductor based PCS reflects wavelengths of 850, 1310 and 1550 nm, when selecting the diameter of the circular rods as 282, 608 and 771 nm, respectively, whereas metal based PCS reflects the aforementioned wavelengths for diameters of the circular rods close to 335, 1070 and 871 nm, respectively. Further, we assayed the variation in reflected wavelength with respect to different diameters of circular rods for both proposed structures. Thus, the proposed optical reflectors can find a wide range of applications vis-à-vis three communication windows.

Ultra-fast tunable optoelectronic half adder/subtractor based on photonic crystal ring resonators covered by graphene nanoshells

This paper reports a new design of a tunable optoelectronic half adder/subtractor. Two photonic crystal (PhC) ring resonators are used to realize the proposed structure. Several silicon rods surrounded by silica rods covered with graphene nanoshells (GNSs) form every PhC ring resonator. Setting the chemical potential of GNS with an appropriate gate voltage, we can tune the PhC resonant mode as desired. The plane wave expansion technique is used to study the photonic band structure of the fundamental PC microstructure, and the finite-difference time-domain method is employed in the final design for solving Maxwell's equations to analyze the light propagation inside the structure. We systematically study the effects of physical parameters on the transmission reflection and absorption spectra. By optimizing the geometric dimensions, resonant absorption peaks can be excited at the same time for GNSs. Our numerical results also reveal the maximum time response is about 0.8 ps. The 200 µm2 area of the proposed half adder/subtractor makes it the building block of every photonic integrated circuit. Also, the design of various fast signal processing systems in optical communication networks is possible due to using tunable GNSs in PhC ring resonators. This study can introduce the use of two-dimensional materials in the design and implementation of logic circuits.

Topology optimization of 3D photonic crystals with complete bandgaps.

The design of photonic crystals with complete bandgaps has recently received considerable research focus for numerous reasons. This work leverages well-known nonlinear programming techniques to alleviate the non-smoothness caused by degenerate eigenvalues such that topology optimization problems can be solved with the open-source IPOPT software. A fully-vectorial plane wave expansion technique is used with an iterative eigensolver to efficiently predict dispersion properties of candidate structures. Nonlinear programming is employed to solve the inverse problem of designing three-dimensional periodic structures that exhibit complete two-dimensional (2D) and three-dimensional (3D) photonic bandgaps. Mesh refinement is performed to alleviate the large computational burden of designing and analyzing photonic crystals, and a periodic density filter is implemented to impose a minimum feature size for manufacturability considerations.

A novel design of fast and compact all-optical full-adder using nonlinear resonant cavities

In this paper, we report a new design of an all-optical full-adder using two nonlinear resonators. The PhC-based full-adder consists of three input ports (A, B, and C for input bits), two nonlinear resonant cavities, several waveguides, and two output ports (for the SUM and CARRY). Eight silicon rods and a nonlinear rod composed of doped glass form each resonant cavity. The well-known plane wave expansion technique is used to calculate the photonic band structure. It shows a wide photonic bandgap in the wavelength range of 1365–2074 nm covering the C and L optical transmission bands. The finite-difference time-domain method is applied to study the light propagation inside the full-adder. Our numerical results demonstrate when the incoming light intensity increases, the nonlinear optical Kerr effect appears and controls the direction of light emitted inside the structure as desired. The maximum time delay and footprint of the proposed full-adder are about 3 ps and 758.5 μm2, respectively. Therefore, due to the low time delay and small footprint, the presented design can be used as a basic mathematical operator in the all-optical arithmetic logic unit.

Realization Of Temperature Measurement Using Semiconductor Based Photonic Crystal Structure

Semiconductor based two-dimensional triangular photonic crystal structures (TPCS) are focused in the present research to measure the temperature where the semiconductors like Silicon, Germanium, Indium Arsenide, and Indium Antimonide are used as the background materials. The triangular strctures are exposed to a light source of wavelength 10.59μm to estimate the temperatures. Since the abosorbtance of the background materials is zero at incident signal,the energy of transmitted light solely depends on the reflected light energy. Further plane wave expansion (PWE) technique has been implemented in analysing the nature of the photonic bandgap (PBG) of the photonic structure which is a decisive factor for the calculation of output energy. The results are obtained by appraising the energy level of transmitted light through the photonic crystal structure.

Analysis of GaN-based 2D Photonic Crystal Sensor for Real-time Detection of Alcohols

The present research proposes an extensive assay of photonic band gap (PBG) characteristics for transverse electric field polarization in two-dimensional (2D) photonic crystal (PhC) structures, with a vision to sense different groups of alcohol like methanol, ethanol, propanol, butanol and phenol. The plane wave expansion (PWE) technique is implemented for realization of PBG in two types of lattice configurations such as square lattice and triangular lattice with circular air holes. Various structure parameters like radius of the circular air holes, lattice constant, nature of the background material, arrangement of air holes and period of air holes are meticulously optimized for envisaging a complete band gap. A variety of unpredicted trends are observed in the simulation outcomes, which include a substantial shift in band gap width, band gap size, reflected wavelength, reflected light intensity and transmitted light intensity for different types of alcohols. Also, the effect of air filling fraction on the band gap size has been investigated by selecting different radius of circular air holes. Apart from this, high sensitivity of 1645 nm/RIU and resolution of $$6.07\times {10}^{-5}$$ RIU is attained with the proposed structures, which pave the path for different bio-sensing applications.

Photonic Crystal and its Application as a Biosensor for the Early Detection of Cancerous Cells

<p>The motivation for this paper is the strikingly sad statistics, obtained from various research bodies globally, regarding the effect of cancers on the global populace and the impact of current methods put in place for the early diagnosis of cancer. This paper is novel for many reasons. Primarily, it presents the use of an optical biosensor based on photonic crystal for cancer cell detection. This biosensor was recently developed as an ultra-compact biochemical sensor based on a 2D photonic crystal cavity known for altering its spectrum in proportion to minute changes in refractive index. Secondarily, The Finite Difference Time Domain (FDTD) and Plane Wave Expansion (PWE) techniques were applied to analyze the possibility of using photonic crystals as biosensors for the detection of cancer cells. The obtained resonant wavelength from the analysis of simulated results was 1.54964 µm and transmitted power obtained from the analysis was 51.9%. For the cancerous cell sample, The PC 12 Cell, the obtained resonant wavelength from analysis of the simulated results was 1.54964 µm and the transmitted power obtained from the analysis was 55.6%.</p>

Studies on Reflectance-Temperature characteristics of AlGaN semiconductor at three communication windows

This paper reports the temperature variation of reflectance with respect to AlGaN wave guide structure. Plane wave expansion technique is employed for simulation to exhibit the reflectance pertaining to AlGaN wave guide structure. The simulation results show the approximate linear variation of reflectance with respect to temperature in the aforementioned AlGaN photonic wave guide structure at threecommunication windows (850 nm, 1310 nm, 1550 nm). Such characteristic study yields with accuracy, the realization of temperaturedependence of reflectance.

3D Waveguides for Nano Photonic Application

Silicon and gallium arsenide (GaAs) based three dimensional photonic structure is realized here to envisage at Terahertz mirror device, which is purely belonged to the application of nano photonic devices. Further plane wave expansion technique pertaining to the mathematical formulation is disclosed in this research to evaluate the photonic bandgap of silicon and gallium arsenaide crystal structure. Aside this, lattice spacing and diameter of air holes of both the structure play key role to understand the above said application, which controls the reflection and transmission of signal . Finally it is revealed that with the proper combination of lattice spacing and diameter of air holes of the said 3D structure determines a range of Terahertz frequency. Finally, the outcome of the paper claims that the proposed structure can be a suitable candidate for nano photonic application.

Analytical studies on FBG based SOI structure for realization of optical interconnect

In this research, fiber based BiFeO3-air structure is lucidly investigated at wavelength of 1.55 μm for optimization of reflectance, diffraction and dispersion loss in order to maximize the transmitted efficiency. Here bismuth ferrite (BiFeO3) is taken as odd layer and air is taken as even layer to realize the SOI waveguide fiber brag structure. Further plane wave expansion (PWE) technique is deployed for simulation of reflectance, whereas diffraction efficiency and dispersion efficiency is simulated through simple numerical formulations. However, numerous structure parameters such as refractive indices and thickness of odd and even layer along with number of fiber bragg layer plays key role to envisage high transmitted efficiency in the proposed structure. Simulation outcomes divulged that very high transmitted intensity is achieved, hence the proposed fiber brag structure can be regarded as a promising candidate as optical interconnect for photonic integrated circuit.

Metamaterial based photonic structure: An alternate high performance antireflection coating for solar cell

Metamaterial based one dimensional photonic grating is thoroughly investigated in this research to realize an anti reflection element pertaining to solar wavelength which can be incorporated with solar cell in lieu of existing antireflection material. To envisage the same, we manipulated with plane wave expansion technique to affirm the negligible reflection of the said grating structure. Furthermore, the simulation outcomes confirm that the proposed nanoscale device reflects a maximum of 10−13 % of solar energy at visible signals which could be an apt candidate for antireflection coating.

Analysis of the Photonic Crystal Power Splitter Based on the Junction Defect Radius for Optimum Resonance

Nano-photonics is an emerging area of optical materials, which would take the optointegrated circuits towards progress. Photonic crystal (PC) based power splitters are useful constituents for the design of photonic integrated circuits (PICs). They are very important devices for connecting different building blocks on an integrated optical chip. In this paper, a two-dimensional PC Y-junction power splitter (21×15 μm) based on the resonance effect with circular air holes etched on a hexagonal lattice with a period a is proposed. The plane wave expansion (PWE) and finite difference time domain (FDTD) techniques are used for analyzing the structure. The simulation results show that the optimum resonance occurs when the radius of the defect hole is 0.3a, leading to the maximum and equal power distribution.

Optical filter based electrical control vis-à-vis cloud data: A new hybrid optoelectronics device for embedded application

A new-fangled optoelectronic device is suggested in present manuscript to control electrical appliances with the help of optical filtering and switching action, pertaining to the signal of 1538 nm, 1548 nm and 1551 nm where, the principle of filtering action is based on reflectance characteristics and the theory of switching action is rooted in Arduino based Proteus simulation which is used to check the entire hardware to realize the controlling action. Further, plane wave expansion technique is employed here to analyze the reflectance characteristics of photonic based filter where, Arduino development board is deployed for hardware interfacing between Matlab and real world. Finally, the aforementioned filtering information manifested in cloud server for the sake of wide dissemination of aforesaid data, which leads to many embedded application.

Realization of tunable optical channel drop filter based on photonic crystal octagonal shaped structure

Photonic crystals (PhCs) are artificial dielectric nanostructure materials. In these structures, a periodic modulation of the material dielectric constant results in a photonic band gap (PBG). By employing defects in the photonic crystals, light can steer in specific direction. Consequently, defects are used in most of the PhC structures. In this work, a novel channel drop filter (CDF) based on two dimensional (2-D) photonic crystal with octagonal shaped structure is designed and numerically analyzed by using the finite difference time domain (FDTD) and plane wave expansion (PWE) techniques. The proposed filter is an octagonal shaped structure of Si rods between two waveguides; consisting of 19*18 silicon rods with the refractive index of 3.5 and rod radius of 0.16a; where a is a lattice constant and equals 0.6 μm. By analyzing the structure, wide ranges of TE photonic band gap (PBG) would be achieved. It will be stated that the proposed CDF has appropriate characteristics and could be used in the future wavelength division multiplexing (WDM) communication systems.

Metamaterial based photonic crystal fiber memory for optical computer

Photonic crystal fiber (PCF) based optical memory is discussed in this communication, which will be useful for optical computer. The proposed PCF is designed by using metamaterial structure, which bestows implausible upshot for envisaging optical memory in computer system. Present report uses two IR signals of 1300 nm and 1575 nm wavelengths to realize the aforementioned memory application, where 1300 nm acts as input signal and 1575 is used as excited signal. Moreover plane wave expansion technique is employed to study the modal analysis of electricfield distribution in the proposed photonic crystal fiber, where the variation of peak electricfield in the fiber is the basic operational principle of present discussion. Finally, this work avows that photonic crystal fiber with apt intrinsic parameters can be a suitable element for optical computer.