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A modified processor array with synchronous optical buses and switches for time division multiplexed optical communications is proposed. Compared with a previously proposed processor array architecture, our architecture features better flexibility, improved packet slot utilization rate and reduced average packet response time, while preserving all-optical communication paths.

Micro-tubes made out of improved lead zirconate titanate (PZT) material are used to develop a new optical switch. These PZT micro-tubes are being manufactured by an electrophoretic deposition process (EPD). EPD overcomes some of the processing problems of other conventional processing techniques. PZT tubes with less than 1mm outer diameter were fabricated successfully with EPD. The analysis of various design concepts and deflection characteristics of the micro-tube show that with an inner diameter of 130 μm and a wall thickness of 330 μm the switching concept is feasible, assuming certain achievable values for the length of the tube, piezoelectric constant and excitation voltage. A test bed for measuring the deflection of the tubes was also developed.

Optical switch prototypes are developed based on the new concept that the input fiber is directly moved by the deflection of a piezoelectric tube actuator. The piezoelectric tube actuators used in the switch prototypes are manufactured by an electrophoretic deposition process. The tubes are low cost and compact in size with an inner diameter of less than 1mm. They have a deflection of 65 µm which is adequate to actuate the input fiber for switching.

A number of multimode 1×2 fiber optical switch prototypes have previously been built. To develop the new 1×4 optical switch, a new output fiber alignment device was fabricated. The conductive coating on the piezoelectric tube actuator was sectored into four. Also, the power supply unit was redesigned in order to provide high voltage for the four-sectored tube. The success in the 1×4 prototype development proves that the new multiple-output piezoelectric switching concept is feasible. The concept demonstrates an advantage over some other opto-mechanical switches which need to be cascaded to achieve a multiple-output configuration.

Photonic crystals (PCs) with infiltrating liquid crystals (LCs) have many potential applications because of their ability to continuously modulate the band-gaps. Using the plane-wave expansion method (PWM), we simulate the band-gap distribution of 2D honeycomb lattice PC with different pillar structures (circle, hexagonal and square pillar) and with different filling ratios, considering both when the LC is used as filling pillar material and semiconductors (Si, Ge) are used in the substrate, and when the semiconductors (Si, Ge) are pillar material and the LC is the substrate. Results show that unlike LC-based triangle lattice PC, optimized honeycomb lattice PC has the ability to generate absolute photonic band-gaps for fabricating optical switches. We provide optimization parameters for LC infiltrating honeycomb lattice PC structure based on simulation results and analysis.

A tunable plasmonic induced transparency (PIT)-based light switching is proposed and investigated. The proposed structure consists of a bus waveguide, two nanoresonators and an optofluidic pump system for actively tuning the system’s transmission. By using the finite difference time domain method, it is found that the interferences between the dark and bright mode resonators can be controlled by manipulating the fluid filled in the resonator, leading to an actively tunable plasmonic switch, the transmittance can be flexibly tuned from near unity to zero. The structure in our paper has the following advantages, such as ultracompact size and easy fabrication. Our study will provide a possibility for designing the ultrafast devices in highly integrated optical circuits.

All-optical switch is one of the key parts of optical circuit. We employ a temperature-sensitive resonator to form an optical switch. The resonator deforms under the applied light and adjusts the transmittance of the structure. To our knowledge, this is the first design of an all-optical surface plasmon polariton (SPP) switch based on the heat deformation effect.

This study introduces a single-layer patterned graphene metamaterial, composed of a graphene ring (GR), two parallel graphene strips (TPGSs), two vertical graphene strips (TVGSs), and a graphene block (GB), which achieves triple plasmon-induced transparency (TPIT) in the terahertz (THz) frequency range using coupled mode theory (CMT) and the finite-difference time-domain (FDTD) technique. Moreover, a synchronized electro-optical switch with four modulation modes is implemented by dynamically adjusting graphene’s Fermi level, exhibiting modulation degrees of amplitude (MDA) of 88.3%, 94.7%, 86.9%, and 89.0% at 1.69THz, 3.14THz, 3.95THz, and 4.67THz, respectively. In addition, the modes excited by TPGSs and TVGSs interconvert due to the proposed structure’s symmetry, accounting for the polarization insensitivity of TPIT. The enhanced MDA and polarization insensitivity of the electro-optical switch presented in this study significantly surpass those of comparable electro-optical switches. As a result, the polarization insensitivity of multiple optical switches to incident light fields offers a promising approach for designing optoelectronic devices.

An all-optical data comparator with the help of Terahertz Optical Asymmetric Demultiplexer (TOAD) is proposed. The paper describes the all-optical data comparator by using a set of all-optical full-adder and optical switch. Comparison between two binary data is required in many data processing systems. It is sometimes necessary to know whether a binary number is greater than, equal to, or less than another number. The all-optical data comparator can be used to perform a fast central processor unit using optical hardware components. In this present communication, we have tried to exploit the advantages of TOAD-based switch to design an integrated all-optical circuit which can perform data comparison operations.

Optical bistability device based on nonlinear one-dimensional photonic crystals is designed and manufactured. The device has 20 periods and is made from ZnS and ZnSe layers alternately. When the incident power density reach threshold power density 1.0 × 10⁵ W/cm², the Ar ion laser, whose wavelength is 514.5 nm, is shifted out of the optical band gap of the one-dimensional nonlinear photonic crystals, so an optical switch is made. It also can be made into an optical bistability device. The threshold power density of the optical bistability is 1.38 × 10⁵ W/cm² and its switching time is about 100 ps in experiment. The experimental results are in good accordance with the theoretical ones.

Nonlinear optics has been of increased interest for all-optical signal, data and image processing in high speed photonic networks. The application of multi-valued (nonbinary) digital signals can provide considerable relief in transmission, storage and processing of a large amount of information in digital signal processing. Here, we propose the design of an all-optical system for some basic tri-state logic operations (trinary OR, trinary AND, trinary XOR, Inverter, Truth detector, False detector) which exploits the polarization properties of light. Nonlinear material based optical switch can play an important role. Tri-state logic can play a significant role towards carry and borrow free arithmetic operations. The principles and possibilities of the design of nonlinear material based tri-state logic circuits are proposed and described.

Comparator determines whether a number is greater than, equals to or less than another number. It plays a significant role in fast central processing unit in all-optical scheme. In all-optical scheme here 1-bit binary comparator is proposed and described by Terahertz Optical Asymmetric Demultiplexer (TOAD) based interferometric switch. Simulation result by Mathcad-7 is also given. Cascading technique of building up the n-bit binary comparator with this 1-bit comparator block is also proposed here.

This paper describes a new model for the breakdown voltage of SiO₂ fiber coupler using the Pockel effect and empirical equation. The model is evaluated by using the coupling coefficient and the changes in the refractive index. We found that the breakdown voltage is in the order of 10² volt corresponding to coupling coefficient by the order of mm^-1. Increasing the value of coupling coefficient between the electrodes leads to a reduction in the breakdown voltage.

We report magneto-optical properties in a kerosene colloidal suspension of oleic acid coated Fe₃O₄ nanoparticles (~14 nm). The magnetic colloids (fluids) show birefringence under a magnetic field. Systematical studies of the on–off switch times upon application of the on–off magnetic field with varied experimental parameters indicate that the switch response time depends strongly on the strength of the magnetic field and the concentration of the magnetic nanoparticles in the fluid. The data can be explained in terms of the formation of magnetic nanoparticle chains under a magnetic field. The important magneto-optical properties of the magnetic fluids allow us to design a tunable optical switch.

The nonlinear optical (NLO) properties of lanthanide bisphthalocyanine (Lu(TBPc)Pc), including first hyperpolarizability, second hyperpolarizability and reverse saturable absorption (RSA), have been investigated. Furthermore, Lu(TBPc)Pc has also been applied for optical switch based on its RSA performance.

This paper describes a new type of optical switch, named as SWOMS (Self-latching Waveguides Optical MEMS Switch). The SWOMS is based on a novel micromachined bistable self-latching structure, which is fabricated on a SOI (silicon-on-insulator) wafer with a 35μm top silicon layer, and with polymer waveguides attached on it. Comparing to existing moving waveguide switches, SWOMS has some unique promising features such as gap-elimination and self-latching. Here, the structure, principle, and fabrication of SWOMS will be introduced.

MEMS (Micro Electro Mechanical Systems) products are being spread from laboratory to industries. But Silicon-based MEMS products are usually expensive and not suitable for low cost production. Hence, there is an emerging need in terms of cost effectiveness to transfer MEMS from silicon-based materials to other materials, such as glasses and polymers. Micro hot embossing is expected to be a novel technique for producing MEMS components/products with low cost, and will potentially find wide applications in micro fluidics, biomedical and micro optical areas. In this paper, a hot embossing instrument is illustrated and is used for the process development of micro/nano structure forming with polycarbonate (PC) and Polyetheretherketone (PEEK) by using the Nickel mold. Fabrications of micro vertical reflecting mirrors and cantilevers for an 8×8 optical switch have been carried out, replication of micro grooves and pyramid cavities with nanometer precision for passive alignment of optical fibers and micro ball lenses have been performed as well. The results show that hot embossing is a promising technology for cost effective micro/nano fabrications of MEMS.

This paper presents an 8×8 optical switch consisting of a micro cantilever array. Each cantilever, with a vertical micro mirror located on one end of it, was driven by electrostatic actuation. The optical switch was fabricated using combined silicon process, electroplating and hot embossing. The optical switch, embossed with a polymer material, was aligned and assembled together with input and output optical fibers via grooves etched on a silicon substrate. Considering the fabrication process and material used, this optical switch is suitable for cost-effective mass production, and will potentially find wide applications for fiber-to-the-home communications.

One of the most critical elements within the framework of wavelength division multiplexing optical network is the optical cross-connect. The core of an optical cross-connect is the optical switch capable of switching a large number of input and output fibers. In this paper, we report the design of a polarization independent liquid crystal optical switch. It is pointed out that liquid crystal spatial light modulator technology is a very competitive technology to realize a large-scale reconfigurable optical switch.

A new process has been presented to fabricate single crystal silicon (silicon) micro mirror switching devices. Silicon torsion and flexural springs have been integrated with a mirror plate for angular displacement amplification. Mirror switching is achieved with a bimorph thermal actuator, which is insensitive to environmental temperature changes and fabricated using surface micro machining layers. The release process combines silicon etching in KOH with sacrificial etching of oxide from backside. The design offers protection for the structure layers from both front and backside. Device demonstrates an angular amplification concept. An angular displacement of 15 degree was achieved.