scholarly journals Investigation On Ultra-Compact, High Contrast Ratio 2d-Photonic Crystal Based All Optical 4 x 2 Encoder

Author(s):  
R. Arun Kumar ◽  
Kavitha V ◽  
Rama Prabha K ◽  
Latha K ◽  
Robinson S

Abstract Optical encoder is playing an essential starring role in optical communication and computing applications. This paper presents a new structure for 4 x 2 optical encoder based on Two Dimensional Photonic Crystals (2DPC). The proposed structure consists of silicon rods in background of air using hexagonal lattice. The proposed structure is composed of four input waveguides and two outputs. The band structure is examined by Plane Wave Expansion (PWE) method and the performance parameters of the 4x2 encoder, namely, normalized output power, footprint, contrast ratio, response time and bit rate are analyzed using Finite Difference Time Domain (FDTD) method. The proposed encoder is operated at 1550nm. The low response time, and small footprint have shown that the encoder is exceptionally suitable for high performance optical networks and photonic computational integrated devices.

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Priyanka Pathak ◽  
Rukhsar Zafar ◽  
Vinay Kanungo ◽  
Sandeep Vyas

AbstractPhotonic crystal waveguides provide a way to manipulate the performance of an optical signal in an ultra-small volume and are quite viable in designing chip-based components that will work all-optically. Here, in this article an all-optical half adder is proposed. It is based on a square lattice photonic crystal waveguide in which silicon rods are arranged periodically. The photonic crystal offers a wide photonic band-gap in the desired region of telecommunication wavelength (i. e. near λ = 1550 nm. The performance of half Adder is measured using the contrast ratio and response time. The contrast ratio for sum and carry is 5.2 dB and 16.7 dB, respectively. The proposed half adder is miniaturized in size and having a footprint of 49 µm2 only. The total response time of the proposed adder is 1.4 picoseconds only. So, the device offers a high bit rate of 0.714 Tb/sec. The proposed half adder is an optimum choice for its application in on-chip optical integrated circuits.


Frequenz ◽  
2020 ◽  
Vol 74 (9-10) ◽  
pp. 277-285
Author(s):  
Mohamed Salah Bouaouina ◽  
Mohamed Redha Lebbal ◽  
Touraya Bouchemat ◽  
Mohamed Bouchemat

AbstractThe all-optical logic gates have become an important key enabling in optical integrated circuits and find applications in optical networks. In this paper, we introduce new complete series of optical logic gates using photonic crystals. These designs formed by compilation with interference based defect and resonance phenomenon. The proposed work based on two dimensional square lattices by putting gallium arsenide (GaAs) rods immersed on air background. The maximum contrast ratio and the maximum working bit rates is obtained for the NOT/XOR and OR logic gates equal to 50.81 dB and 12.5 Tb/s, respectively. The simulation and optimization of structure is approved out using Finite-Difference-Time-Domain (FDTD) method and Plane Wave’s Method (PWEM).


Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 874
Author(s):  
Soyoung Bae ◽  
Youngno Kim ◽  
Jeong Min Kim ◽  
Jung Hyun Kim

MXene, a 2D material, is used as a filler to manufacture polymer electrolytes with high ionic conductivity because of its unique sheet shape, large specific surface area and high aspect ratio. Because MXene has numerous -OH groups on its surface, it can cause dehydration and condensation reactions with poly(4-styrenesulfonic acid) (PSSA) and consequently create pathways for the conduction of cations. The movement of Grotthuss-type hydrogen ions along the cation-conduction pathway is promoted and a high ionic conductivity can be obtained. In addition, when electrolytes composed of a conventional acid or metal salt alone is applied to an electrochromic device (ECD), it does not bring out fast response time, high coloration efficiency and transmittance contrast simultaneously. Therefore, dual-cation electrolytes are designed for high-performance ECDs. Bis(trifluoromethylsulfonyl)amine lithium salt (LiTFSI) was used as a source of lithium ions and PSSA crosslinked with MXene was used as a source of protons. Dual-Cation electrolytes crosslinked with MXene was applied to an indium tin oxide-free, all-solution-processable ECD. The effect of applying the electrolyte to the device was verified in terms of response time, coloration efficiency and transmittance contrast. The ECD with a size of 5 × 5 cm2 showed a high transmittance contrast of 66.7%, fast response time (8 s/15 s) and high coloration efficiency of 340.6 cm2/C.


2014 ◽  
Author(s):  
Marco Fiorentino ◽  
Chin-Hui Chen ◽  
Géza Kurczveil ◽  
Di Liang ◽  
Zhen Peng ◽  
...  

Nanoscale ◽  
2015 ◽  
Vol 7 (47) ◽  
pp. 20249-20255 ◽  
Author(s):  
Sheng Gan ◽  
Chuantong Cheng ◽  
Yaohui Zhan ◽  
Beiju Huang ◽  
Xuetao Gan ◽  
...  

A simple method to fabricate thermo-optic modulators with high performance in a small footprint.


2021 ◽  
Vol 2086 (1) ◽  
pp. 012166
Author(s):  
D A Savelyev

Abstract The diffraction of vortex laser beams with circular polarization by ring gratings with the variable height was investigated in this paper. Modelling of near zone diffraction is numerically investigated by the finite difference time domain (FDTD) method. The changes in the length size of the light needle and focal spot size are shown depending on the type of the ring grating.


2014 ◽  
Vol 25 (1) ◽  
pp. 169-185
Author(s):  
Samuel Ángel Jaramillo Flórez ◽  
Yuli Fernanda Achipiz

The bioelectronics takes of the biology the optimized elements for to do a copy and to build technological mechanisms with functions based in that of body lives components. Telecommunications and biology present an analogy between the optical receivers and insects eyes, which forms are adequate to receipt signal since a transmitter, and these are been leaded to perfection by the nature during millions of years in the environment adaptation. The sizes and the forms depend of the direction of the waves and of the radiation pattern of these biotransmitters and bioreceivers (omatidies of insects eyes), which is similar as the optical communications emitters and photodetectors. The growth of the telecommunication services makes necessary the optimization of the bandwidth of the transmission channels. Although the optic transmission is considered like the ideal as for the attenuation and distortion characteristics that make that it possesses the better relation bandwidth - longitude, the demand of more transmission capacity forces to take advantage of them efficiently. High costs generated when deploying Optic Fiber Networks at the transport level, together with other factors that avoid PONs arriving to the home and/or office, have impulsed the design and implementation of partially optical networks (FITL), including an alternative that uses infrared light. This work explores the basis of these news access networks, and it is presented an optical communication transmission/reception system with optic channel of free space where has been modulated the transmitter laser through a set of spherical lens and optical fibers that expand the beam of light to different points of an indoor enclosure producing multiple punctual images located in positions that permit to determine and to optimize the bandwidth of the system. The computational simulation results are showed and are compared with those experimentally measured, indicating that this is an original method for to design emitters and receivers of high performance for optical communications.


Crystals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 461 ◽  
Author(s):  
Mohammad Reza Jalali Azizpour ◽  
Mohammad Soroosh ◽  
Narges Dalvand ◽  
Yousef Seifi-Kavian

In this paper, an all-optical photonic crystal-based switch containing a graphene resonant ring has been presented. The structure has been composed of 15 × 15 silicon rods for a fundamental lattice. Then, a resonant ring including 9 thick silicon rods and 24 graphene-SiO2 rods was placed between two waveguides. The thick rods with a radius of 0.41a in the form of a 3 × 3 lattice were placed at the center of the ring. Graphene-SiO2 rods with a radius of 0.2a were assumed around the thick rods. These rods were made of the graphene monolayers which were separated by SiO2 disks. The size of the structure was about 70 µm2 that was more compact than other works. Furthermore, the rise and fall times were obtained by 0.3 ps and 0.4 ps, respectively, which were less than other reports. Besides, the amount of the contrast ratio (the difference between the margin values for logics 1 and 0) for the proposed structure was calculated by about 82%. The correct switching operation, compactness, and ultra-fast response, as well as the high contrast ratio, make the presented switch for optical integrated circuits.


Sign in / Sign up

Export Citation Format

Share Document