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.
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.
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.
Reduction in dimensions of CMOS technology has resulted in great increase in computing speeds but, at the same time, higher power consumption. Thus, a serious limitation arises since conventional approaches will eventually hit the physical limit [1], [2]. Reversible computing seems promising in the context of VLSI. In theory, it could operate without any energy loss due to lossless information processing [3], [4]. The paper presents development and implementation of a reversible Arithmetic Logic Unit (ALU) based on quantum logic gates working with qubits. The architecture is based on Fredkin gates (quantum cost 5) and CNOT gates (quantum cost 1), both preserving parity and being inherently reversible. The ALU can execute all arithmetic and logical operations and reconfigure operations dynamically according to system requirements. Also, the designed ALU possesses an inherent parity-preserving fault detection mechanism for reliable identification of single-bit faults. Overall the implemented ALU contains 9 CNOT and 7 Fredkin gates resulting in quantum cost equal to 44 and 12 garbage outputs. Thus, the quantum cost and garbage outputs are significantly lower than usual ones for the design of a reversible ALU, which generally amount to 48–65 and 16–20 correspondingly. The designed architecture is described in details through the application of Verilog HDL and simulation in Xilinx Vivado toolset. The work concentrates on optimization of such important parameters as the number of gates, quantum cost, garbage outputs, and constant inputs. Those design parameters are critical in order to develop scalable and sustainable quantum and low-power VLSI architectures.
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.
Information loss is generally related to power consumption. Therefore, reducing information loss is an interesting challenge in designing digital systems. Quaternary reversible circuits have received significant attention due to their low-power design applications and attractive advantages over binary reversible logic. Multiplexer and demultiplexer circuits are crucial parts of computing circuits in ALU, and their efficient design can significantly affect the processors’ performance. A new scalable realization of quaternary reversible4×1multiplexer and1×4demultiplexer, based on quaternary 1-qudit Shift, 3-qudit Controlled Feynman, and 2-qudit Muthukrishnan-Stroud gates, is presented in this paper. Moreover, the corresponding generalized quaternary reversiblen×1multiplexer and1×ndemultiplexer circuits are proposed. The comparison, with respect to the current literature, shows that the proposed circuits are more efficient in terms of quantum cost, the number of garbage outputs, and the number of constant inputs.
To meet expectations of the futuristic technologies, thrust is on fast communication, low power, high computational speeds with delay intolerance. VLSI technology is laboring to meet the demands by incorporating low-power solutions to improve performance. Component size has come to Nano scales however, it has challenges of managing heat dissipation and physical limitations in fabrication. Reversible logic technology has gained momentum in research due to its prominence in Quantum computing and zero power dissipation. The arithmetic and Logic Unit is the significant component of any computing architecture, carrying out operations rigorously while consuming power for the endurance of performance. The proposed approach of designing the fault-tolerant Arithmetic and Logical Unit (ALU) in reversible logic for future computers. Analysis of the proposed design to existing designs is on the quantum cost (QC), garbage output (GO), ancilla input (AI), gate utilization (GC) and number of operations achieved. Improvements observed is at an average of 70% in AI and GC, 59% in QC , 53% in GO and operations are up by 33% to cater to the least power consumption applications.
In recent years, reversible logic has emerged as a promising technology withapplications spanning low-power CMOS, quantum computing, nanotechnology, andoptical computing. Quantum computing, in particular, relies on reversible logic for itsrealization. The construction of low-power and low-loss computational structures iscrucial for developing arithmetic circuits used in quantum computation, nanotechnology,and other low-power digital circuits. This work presents optimized one-digit BCD addersand carries skip BCD adders using new reversible logic gates. The proposed approachaims to minimize quantum cost and optimize performance compared to existing circuits,focusing on reducing the number of reversible gates used and minimizing garbage outputsproduced. The objective is to design faster BCD adders and provide a foundation forbuilding the decimal Arithmetic Logic Unit (ALU) of a Quantum CPU. The work isimplemented using Hardware Description Language (HDL), with Simulation & Synthesisconducted on Xilinx ISE. The design targets the Xilinx Spartan 3E FPGA device. Thisresearch contributes to the advancement of efficient and high-performance arithmeticcircuits suitable for emerging technologies such as quantum computing andnanotechnology.