Implementation of 2 Qubit Quantum Arithmetic Logic Unit on Qiskit

This paper describes the design and development of a 2-bit Quantum Arithmetic Logic Unit (ALU) with Qiskit. The ALU executes arithmetic operations—addition, two’s complement subtraction, multiplication—and logical operations such as AND, OR, and XOR, controlled by a special unit. The design optimizes qubit utilization for compatibility with noisy intermediate-scale quantum (NISQ) devices. The operations were manually tested through simulations to ensure that the quantum circuits functioned as intended. The presented work illustrates the applicability of classical ALU concepts to quantum computing architectures and lays the ground for scalable quantum processors.