The NAND, NOT, and NOR logic gates which are utilised to realise the hardware modules of the system, are examples of basic classical logic gates that make up the hardware basics of electronic circuit systems. In addition to this, a useful system has been described for designing and implementing quantum processors by using reversible logic gates to analyse the performance of ALUs. Additionally, it shows that QCA might be used in quantum computers, assuming that the underlying technology can be made workable. When considering energy-efficient computations, reversible or information-lossless circuits are crucial for digital signal processing, communication, computer graphics, and cryptography. By preventing information loss, reversible logic is utilised to lessen the power dissipation that occurs in classical circuits, which is particularly promising because it allows for extremely low power computations like nano-computing for quantum processors. Because bits of information are lost during logic operations, typical digital circuits waste a lot of energy. It is well known that an Arithmetic and Logical Unit is one of the most fundamental operational units in the quantum processor (ALU). The design and implementation of an innovative r/q 16-bit ALU that improves the overall performance of quantum processors while carrying out the task in the digital signal processing domain are discussed in this study. When reversible gates were used in place of logic gates, the power dissipation in terms of information bit loss was significantly reduced. Simulation of these circuits is done by QCA Designer tool and language used for programming is very high-speed hardware integrated circuit hardware descriptive language, Verilog HDL. The power and delay analysis of the various sub modules is performed and a comparison with the traditional circuits is also carried out. The designed ALU has better efficiency as it has less power loses and reduction in power loss upto 39 % is obtained.
The NAND, NOT, and NOR logic gates which are utilised to realise the hardware modules of the system, are examples of basic classical logic gates that make up the hardware basics of electronic circuit systems. In addition to this, a useful system has been described for designing and implementing quantum processors by using reversible logic gates to analyse the performance of ALUs. Additionally, it shows that QCA might be used in quantum computers, assuming that the underlying technology can be made workable. When considering energy-efficient computations, reversible or information-lossless circuits are crucial for digital signal processing, communication, computer graphics, and cryptography. By preventing information loss, reversible logic is utilised to lessen the power dissipation that occurs in classical circuits, which is particularly promising because it allows for extremely low power computations like nano-computing for quantum processors. Because bits of information are lost during logic operations, typical digital circuits waste a lot of energy. It is well known that an Arithmetic and Logical Unit is one of the most fundamental operational units in the quantum processor (ALU). The design and implementation of an innovative r/q 16-bit ALU that improves the overall performance of quantum processors while carrying out the task in the digital signal processing domain are discussed in this study. When reversible gates were used in place of logic gates, the power dissipation in terms of information bit loss was significantly reduced. Simulation of these circuits is done by QCA Designer tool and language used for programming is very high-speed hardware integrated circuit hardware descriptive language, Verilog HDL. The power and delay analysis of the various sub modules is performed and a comparison with the traditional circuits is also carried out. The designed ALU has better efficiency as it has less power loses and reduction in power loss upto 39 % is obtained.
Reversible computing has emerged as a promising solution for reducing energy dissipation in digital systems by addressing the fundamental limitations caused by information loss.Quaternary reversible logic, which uses multi-valued representations, provides higher information density, reduced interconnect complexity, and better scalability when compared to conventional binary logic.This work presents the design and implementation of a quaternary reversible Arithmetic Logic Unit (ALU) that integrates essential computational modules, including arithmetic units, logical units, memory units, decoders, and multiplexers.The proposed architecture supports efficient data routing and precise operation control through a scalable control unit and a selection-line-based design approach.The designed ALU demonstrates reduced quantum cost, fewer garbage outputs, and minimized constant inputs in comparison with existing reversible ALU designs, while remaining compatible with larger reversible and quantum computing architectures.Simulation results and comparative analysis validate the improved efficiency and low-power potential of the proposed system, making it suitable for next-generation computing applications.The complete design is implemented using Verilog HDL and synthesized and simulated using Xilinx Vivado Design Suite 2025.
This paper presents novel one bit arithmetic and logical unit (ALU) design using basic reversible gates. Two designs for both the arithmetic and the logical unit are proposed and one design for the control unit is also put forward. These designs are integrated together to give four complete ALU designs. Each of the proposed design has been implemented in Verilog HDL using Xilinx ISE Suite 14.1 software to verify its functionality. The proposed designs are compared based on quantum cost, garbage outputs and ancilla inputs with their existing counterparts. The simplicity and the reduced quantum cost of the proposed ALU designs, when compared to the existing ones, makes them ideal candidates to be used as modules in quantum computers. The proposed ALUs extend their applications to cryptography, machine learning and nanotechnology.
Reversible logic technology has the most promising role in quantum computing. With the evolution of high-performance computing devices, future processors are focusing on quantum technology for their development and fabrication. This work focuses on the development of a novel digital processor with memory via parity-preserving reversible logic gates and quantum cellular automaton (QCA). The design and realization of the integral components of the digital processor have been performed with reversible KMD gates. The processor’s main modules include the ALU, multipliers, floating-point division unit, control unit, and memory unit. It has a control unit to monitor and control the operation of the processor. The QCA design of individual modules of the developed processor is carried out with appropriate multilayer wire crossing. The performances of the individual models of the processor are compared and analyzed with those of existing designs. The reversible processor has 891 quantum costs, 141 constant inputs, and 188 garbage outputs; it needs 120 reversible gates and 1397 total costs. The results show that the developed processor modules are better than the existing modules, as the appropriate use of reversible logic gates for modern-day high-performance, economical and low-power-consumption processors.
The effects of quantum mechanics dominate nanoscale devices, where Moore’s law no longer holds true. Additionally, with the recent rapid development of quantum computers, the development of reversible gates to overcome the problems of energy and information loss and the nano-level quantum-dot cellular automata (QCA) technology to efficiently implement them are in the spotlight. In this study, a full adder-subtractor, a core operation of the arithmetic and logic unit (ALU), the most important hardware device in computer operations, is implemented as a circuit capable of reversible operation using QCA-based reversible gates. The proposed circuit consists of one reversible QCA gate and two Feynman gates and is designed as a multi-layer structure for efficient use of area and minimization of delay. The proposed circuit is tested on QCADesigner 2.0.3 and QCADesigner-E 2.2 and shows the best performance and lowest energy dissipation. In particular, it shows tremendous improvement rates of 180% and 562% in two representative standard design cost indicators compared to the best existing studies, and also shows the highest circuit average output polarization.
At present days , reversible logic circuits have many applications in the field of optical information processing, digital signal processing , nano technology and quantum computing . Reversible logic plays an important role when computations with minimum energy dissipation are considered. The purpose of designing reversible logic is to decrease the number of area, power, garbage outputs , constant inputs, quantum cost, reversible gates, delay and hardware complexity . This paper reveals a review on some reversible logic gates, which is useful in designing more complex systems having reversible circuits and can do execution of more complex operations using quantum computers. In upcoming days digital technology will be using reversible logic gates in order to reduce the propagation delay and power consumption as it provides negligible loss of information in the circuit. Keywords: Reversible Gate, Garbage output, quantum cost, Reversible logic, Power dissipation
Reversible logic provides a foundation for nextgeneration computing systems, particularly in quantum and emerging nanotechnology-based architectures. Unlike conventional logic, reversible gates preserve information and support backward computation, making them crucial for designing quantum circuits. This paper introduces a reversible Arithmetic and Logic Unit (ALU) that performs eight fundamental operations-AND, OR, NOT, XOR, addition, subtraction, increment, and decrement-using Fredkin, Peres, TR, and modified Fredkin gates. A dedicated control unit manages operation selection, ensuring functional flexibility and circuit efficiency. The proposed design achieves significant improvements by minimizing ancilla inputs, quantum cost and garbage outputs, resulting in a total quantum cost of 71 and contains 16 reversible gates and 14 garbage outputs. The architecture was modeled and verified using Xilinx Vivado HLS and ISE 14.7, and implemented on the Nexys A7 (Artix-7) FPGA platform. Comparative analysis demonstrates better efficiency than existing reversible ALU designs, establishing the proposed circuit as a strong candidate for quantum computing and other advanced computing paradigms.