Physical Qubits Estimation for Quantum S-Box

We estimate the physical qubits required to implement S-boxes of various sizes on a real quantum processor based on target error rates. Quantum circuits are designed to use fewer quantum resources considering the feasibility of implementation. Qubits are one of the main quantum resources and inherently involve errors. In order to obtain accurate computational results, qubit errors should be minimized. To reduce qubit errors, a large number of physical qubits are required, which is inversely proportional to the target error rate. In this paper, we estimate the number of physical qubits required to implement quantum S-boxes of various sizes. Based on the analysis results, we propose a new metric to optimize the design of quantum circuits.