Carbon disulfide is the most popular material for applications of nonlinear optical (NLO) liquids, and is frequently used as a reference standard for NLO measurements. Although it has been the subject of many investigations, determination of the third-order optical nonlinearity of CS2 has been incomplete. This is in part because of several strong mechanisms for nonlinear refraction (NLR), leading to a complex pulse width dependence. We expand upon the recently developed beam deflection technique, which we apply, along with degenerate four-wave mixing and Z-scan, to quantitatively characterize (in detail) the NLO response of CS2, over a broad temporal range, spanning 6 orders of magnitude (∼32  fs to 17 ns). The third-order response function, consisting of both nearly instantaneous bound-electronic and noninstantaneous nuclear contributions, along with the polarization and wavelength dependence from 390 to 1550 nm, is extracted from these measurements. This paper provides a self-consistent, quantitative picture of the third-order NLO response of liquid CS2, establishing it as an accurate reference material over this broad temporal and spectral range. These results allow prediction of the outcome of any NLR experiment on CS2.

https://apps.dtic.mil/dtic/tr/fulltext/u2/a617213.pdf

Temporal, Spectral, and Polarization Dependence of the Nonlinear Optical Response of Carbon Disulfide

A new and novel scheme for a high speed all-optical half adder based on single Quantum-dot semiconductor optical amplifier (QD-SOA) assisted Mach-Zehnder interferometer (MZI) is theoretically investigated and discussed. In this proposed scheme, pair of input data streams are simultaneously drive the switch to produce sum and carry. In this new design, only single switch can be utilized to design half adder circuit and no additional input beam is required other than two input signals. This design is simpler, smaller and compact than our previously proposed design . The impact of the peak data power as well as of the QD-SOAs current density and maximum modal gain on the ER, Q factor with current densities and electron relaxation times etc are explored and assessed by means of numerical simulations.

Designing of Optimized All-Optical Half Adder Circuit Using Single Quantum-Dot Semiconductor Optical Amplifier Assisted Mach-Zehnder Interferometer

This paper obtains the solitary wave solution of the Bona-Chen equation which is a coupled system of nonlinear evolution equation that arises in the study of shallow water waves flow. The ansatz method and Jacobi elliptic function method are used to obtain the solutions. The conservation law of the equation is obtained by the multiplier method. Finally, the numerical simulations are also given.

Solitary waves and conservation laws of Bona-Chen equations

Logic gates are the fundamental building blocks of digital systems. Using these logic gates, one can perform different logic and arithmetic operations. All-optical logic and arithmetic operations are very much expected in high-speed communication systems. In this paper, we present a model to perform addition/subtraction operations on two binary digits based on a terahertz optical asymmetric demultiplexer (TOAD). Using four TOAD-based switches, we have designed a half-adder and half-subtractor circuit. The approach to designing all-optical arithmetic circuits not only enhances the computational speed but is also capable of synthesizing light as inputs to produce the desired outputs. The main advantages of this circuit are that synchronization between inputs is eliminated and simultaneous addition and subtraction operations are realized at the outputs. This circuit is designed theoretically and verified through numerical simulations. The impact of the control pulse energy, gain recovery time, and the input data pulse width on the extinction ratio, contrast ratio, amplitude modulation, Q-factor, and relative opening of the pseudo-eye diagram of the switching outcome is explored and assessed by means of numerical simulations.

All-optical half-adder/half-subtractor using terahertz optical asymmetric demultiplexer.

Since last few decades optics has already proved its strong potentiality for conducting parallel logic, arithmetic and algebraic operations due to its super-fast speed in communication and computation. So many different logical and sequential operations using all optical frequency encoding technique have been proposed by several authors. Here, we have keened out all optical dibit representation technique, which has the advantages of high speed operation as well as reducing the bit error problem. Exploiting this phenomenon, we have proposed all optical frequency encoded dibit based XOR and XNOR logic gates using the optical switches like add/drop multiplexer (ADM) and reflected semiconductor optical amplifier (RSOA). Also the operations of these gates have been verified through proper simulation using MATLAB (R2008a).

A Novel Approach to Realize of All Optical Frequency Encoded Dibit Based XOR and XNOR Logic Gates Using Optical Switches with Simulated Verification

Optics is regarded undoubtedly a potential and successful candidate in information and data processing because of its inherent parallelism. In last few decades several all-optical data processors, algebraic processors, arithmetic processors are proposed. Here in this communication the authors propose a completely new scheme for implementing binary data arithmetic in 2’s Complement method which is the most advantageous among all other established subtraction methods. To implement it we use non-linear material massively.

An all-optical integrated system for implementing arithmetic operation in 2's complement method with the active participation of non-linear material based switches

A new approach to all-optical half-adder by utilizing semiconductor optical amplifier based MZI wavelength converter

Electronically tunable third-order dual-mode quadrature sinusoidal oscillators employing VDCCs and all grounded components

This paper presents two new analog multipliers/dividers using a new universal active element, called the current differencing buffered amplifier (CDBA). The reported circuits are suitable for monolithic chip realization for use in battery-powered, portable electronic equipments. The circuits can be used as a multiplier and divider without changing circuit topologies. The workability of the proposed configurations is tested through different applications with PSPICE simulations using TSMC 0.35 μm CMOS process parameters. The simulated results show that: for ±2.5 V power supply, the total harmonic distortions are less than 3.1% and 2.25% for the first and second configuration respectively. It also shows that the −3 dB bandwidths are 59.09 MHz and 68.55 MHz and static power dissipations are 0.28 mW and 0.23 mW respectively. The sensitivity of the output of the circuits is low with respect to temperature variations.

Two new analog multipliers/dividers employing single current differencing buffer amplifier

This paper presents new realizations of second order voltage mode and current mode universal filters based on a recently reported active element, called the differential voltage current controlled conveyor transconductance amplifier (DVCCCTA). The proposed circuits do not use external resistor. The filter circuits provide all the responses without changing the circuit topology. All the capacitors are virtually grounded. The use of grounded capacitors makes the circuit suitable for monolithic implementation. The pole frequency and quality factor can be adjusted independently with the input bias currents. The non-ideal analysis and the sensitivity analysis have been included. Both the active and passive sensitivities are not more than unity. The filter performances are verified using the PSpice simulations which agree well with theoretical value. 

/pdf/universal-biquadratic-filter-employing-single-differential-vjsawj7v1b.pdf

Radha Raman Pal

Papers

An all-optical integrated system for implementing arithmetic operation in 2's complement method with the active participation of non-linear material based switches

A new approach to all-optical half-adder by utilizing semiconductor optical amplifier based MZI wavelength converter

Electronically tunable third-order dual-mode quadrature sinusoidal oscillators employing VDCCs and all grounded components

Two new analog multipliers/dividers employing single current differencing buffer amplifier

Universal Biquadratic Filter Employing Single Differential Voltage Current Controlled Conveyor Transconductance Amplifier