Design of reversible Feynman and double Feynman gates in quantum-dot cellular automata nanotechnology

Purpose This paper aims to propose the reversible Feynman and double Feynman gates using quantum-dot cellular automata (QCA) nanotechnology with minimum QCA cells and latency which minimizes the circuit area with the more energy efficiency. Design/methodology/approach The core aim of the QCA nanotechnology is to build the high-speed, energy efficient and as much smaller devices as possible. This brings a challenge for the designers to construct the designs that fulfill the requirements as demanded. This paper proposed a new exclusive-OR (XOR) gate which is then used to implement the logical operations of the reversible Feynman and double Feynman gates using QCA nanotechnology. Findings QCA designer-E has been used for the QCA designs and the simulation results. The proposed QCA designs have less latency, occupy less area and have lesser cell count as compared to the existing ones. Originality/value The latencies of the proposed gates are 0.25 which are improved by 50% as compared to the best available design as reported in the literature. The cell count in the proposed XOR gate is 11, while it is 14 in Feynman gate and 27 in double Feynman gate. The cell count for the proposed designs is minimum as compared to the best available designs.

A Synthetic Genetic Reversible Feynman Gate in a Single E.coli Cell and its Application in Bacterial to Mammalian Cell Information Transfer

Reversible computing is a nonconventional form of computing where the inputs and outputs are mapped in a unique one-to-one fashion. Reversible logic gates in single living cells have not been demonstrated. Here, we created a synthetic genetic reversible Feynman gate in a single E.coli cell. The inputs were extracellular chemicals, IPTG and aTc and the outputs were two fluorescence proteins EGFP and E2-Crimson. We developed a simple mathematical model and simulation to capture the essential features of the genetic Feynman gate and experimentally demonstrated that the behavior of the circuit was ultrasensitive and predictive. We showed an application by creating an intercellular Feynman gate, where input information from bacteria was computed and transferred to HeLa cells through shRNAs delivery and the output signals were observed as silencing of native AKT1 and CTNNB1 genes in HeLa cells. Given that one-to-one input-output mapping, such reversible genetic systems might have applications in diagnostics and sensing, where compositions of multiple input chemicals could be estimated from the outputs.

A New Cost-Efficient Design of a Reversible Gate Based on a Nano-Scale Quantum-Dot Cellular Automata Technology

Quantum-dot cellular automata (QCA) nanotechnology is a practical suggestion for replacing present silicon-based technologies. It provides many benefits, such as low power usage, high velocity, and an extreme density of logic functions on a chip. In contrast, designing circuits with no waste of information (reversible circuits) may further reduce energy losses. The Feynman gate has been recognized as one of the most famous QCA-based gates for this purpose. Since reversible gates are significant, this paper develops a new optimized reversible double Feynman gate that uses efficient arithmetic elements as its key structural blocks. Additionally, we used several modeling principles to make it consistent and more robust against noise. Moreover, we examined the suggested model and compared it to the previous models regarding the complexity, clocking, number of cells, and latency. Furthermore, we applied QCADesigner to monitor the outline and performance of the proposed gate. The results show an acceptable improvement via the designed double Feynman gate in comparison to the existing designs. Finally, the temperature and cost analysis indicated the efficiency of the proposed nan-scale gate.

Utilization of LTEx Feynman Gate in Designing the QCA Based Reversible Binary to Gray and Gray to Binary Code Converters

Aims: The Quantum-dot Cellular Automata explores a unique perspective in the arena of the architectural design of future quantum computers, precisely due to its ultra-low packing density, high operating speed, and low power dissipation. On the other side, reversible computing allows the implementation of extreme low power-consuming circuits by avoiding energy dissipation during the time of computation. Objective: In this paper, we have explored the QCA design of reversible binary to gray and gray to binary code converters based on the application of a unique model of Feynman gate using the layered T exclusive-OR module (abbreviated in this work as LTEx Feynman gate). Methods: We have proposed algorithms to produce multi-control reversible binary to gray and gray to binary code converters and to develop cost-efficient QCA layouts. Results: Our systematic literature survey on the existing QCA designs of reversible binary to gray and gray to binary code converters helped us to compare and analyze the proposed design with the existing ones and identify it as the best design in terms of reversible, and QCA design metrics. Conclusion: Significant improvements in design metrics owing to successful experimentations over the previous designs are reported while instantiating 3X3,4X4, and 8X8 counterpart layouts.

Design of Quantum Cost and Delay Optimized Code Converter Using New Reversible Quantum Circuit Block (QCB)

Background: In this article, we have proposed a new reversible quantum circuit block along with the quantum cost (QC), constant input (CI), garbage output (GO) and delay optimized code converterusing quantum circuit block. Method: Initially, new quantum circuit block has been designed and later reversible code converter circuits have been implemented using it. The proposed new quantum blockused to design 2’s complement code converter (2SCCC), cost efficient BCD to Excess-3 code converter (BECC) and can also be used to implement different logic functions. The QC of proposed quantum circuit block is 8. The QC and delay of the proposed 2SCCC is 8 and 1 respectively. Similarly, the QC and delay of the proposed BECC is 11 and 2 respectively. The proposed cost efficient BECC is designed using two NOT gate, one Feynman gate and one new quantum circuit block with QC is 11. Results: The improvement of QC for 2SCCC and BECC are 27.27 % and 21.43% respectively. The improvement of delay for 2SCCC and BECC are 66.67% and 50% respectively compared with respect to the latest reported results. Conclusion: So the improvement of QC and delay are very high using QCB.

Design of Combinational Circuits Using Reversible Decoder in Tanner Tools

Reversible logic is the emerging field for research in present era. The aim of this paper is to realize different types of combinational circuits like full-adder, full-subtractor, multiplexer and comparator using reversible decoder circuit with minimum quantum cost. Reversible decoder is designed using Fredkin gates with minimum Quantum cost. There are many reversible logic gates like Fredkin Gate, Feynman Gate, Double Feynman Gate, Peres Gate, Seynman Gate and many more. Reversible logic is defined as the logic in which the number output lines are equal to the number of input lines i.e., the n-input and k-output Boolean function F(X1,X2,X3, ...,Xn) (referred to as (n,k) function) is said to be reversible if and only if (i) n is equal to k and (ii) each input pattern is mapped uniquely to output pattern. The gate must run forward and backward that is the inputs can also be retrieved from outputs. When the device obeys these two conditions then the second law of thermo-dynamics guarantees that it dissipates no heat. Fan-out and Feed-back are not allowed in Logical Reversibility. Reversible Logic owns its applications in various fields which include Quantum Computing, Optical Computing, Nano-technology, Computer Graphics, low power VLSI etc. Reversible logic is gaining its own importance in recent years largely due to its property of low power consumption. The comparative study in terms of garbage outputs, Quantum Cost, numbers of gates are also presented. The Circuit has been implemented and simulated using Tannaer tools v15.0 software.

Design and Development of 4-Bit Gray Code Counter Circuit Using Reversible Logic Gate

Aim: This paper proposed the design and development of 4-Bit Gray Code Counter Circuit Using Reversible Logic Gate. Method : The 4-Bit Gray Code Counter Circuit can be design using SAM gate, Feynman gate (FG), double Feynman gate (DFG) and NOT gate. The proposed circuit is the combined application of 4-bit binary asynchronous counter and 4-bit binary to gray code converter circuit. Results:: The proposed gray code counter is designed using four no. of SAM gate, three no. of DFG, one FG and seven reversible NOT gate. The QC, GO and CI of proposed circuit are correspondingly 30, 4 and 7.

Investigations with Reversible Feynman Gate and Irreversible Logic Schematics

In the contemporary world there is enormous hike in communication engineering applications, outcome with massive heat dissipation from the processing nodes. So energy efficient information network is one of paramount issue nowadays. For that optical reversible computing could be a landmark with base as optical logic gate. Reduction in power dissipation, consumption could be accomplished through a blend of reversible and irreversible optical processing and the nodes may recuperate the data. Accordingly, in this article two designs with semiconductor optical amplifier, used as Mach–Zehnder interferometer based all optical reversible Feynman gate, irreversible AND logic gate within a single photonic circuit has been proposed. The output waveforms for AND logic operation, Feynman logic the P (data output identical to input), Q (A ⊕ B) has been verified at 100 Gbps data rate. The designs have been evaluated on the basis of key parameter extinction ratio factor. Numerical simulations have inferred excellent ER performance with design-2(ER>13 dB) in contrast to design-1(ER as 10.2 dB). Performance evaluations for significant deign parameters as pump current, length, width, carrier transport, confine and current injection factor yielded excellent performance. This evaluation could be an assist toward design of contemporary optical networks.