Optimizing Reversible Quantum Circuits for Quantum One-Time Pad Encryption

This paper presents an ۸-qubit quantum circuit with a Galois field due to its fault tolerance, it uses the square algorithm and a low-depth reversible quantum square circuit and its optimized Clifford+T implementation, with emphasis on noise robustness and resource efficiency. Fidelity is evaluated under a standard depolarizing noise model applied to single-qubit Hadamard gates. Simulation results show that the circuit maintains a fidelity above ۰.۹۵ even at a noise rate of p=۰.۰۵, which is mainly attributed to its constant shallow depth of approximately three layers and the predominance of Clifford gates. Resource analysis indicates that a naive implementation of squaring modulo ۲^n exhibits quadratic T-count scaling, whereas the optimized construction achieves a reduction of about ۵۰-۶۰% in T-gate usage without compromising functionality. Circuit depth comparisons further demonstrate that the mod-۸ square circuit preserves a constant depth, while optimized mod-۲^n designs significantly reduce depth compared to naive counterparts. These results highlight the suitability of the proposed circuit for NISQ devices and fault-tolerant architectures, particularly in arithmetic-based quantum cryptographic applications.

کلیدواژه ها:

Galois field ، clifford+T ، algorithm square ، noise ، Quantum One-Time Pad