Quantum-Enhanced Adversarial Defense: A Hybrid Machine Learning Framework for Post-Quantum Cybersecurity

The emergence of quantum computing introduces significant challenges to traditional cybersecurity mechanisms, requiring innovative approaches for post-quantum environments. The main purpose of the study is to design a Quantum-Enhanced Adversarial Defense (QEAD) framework that integrates Quantum Machine Learning (QML) with Adversarial Deep Learning (ADL) to detect both classical and quantum-level cyberattacks. The research utilizes a simulated dataset containing post-quantum attack vectors and evaluates three models: Classical Deep Learning (DL), Quantum ML, and the proposed Hybrid QEAD. The experimental results show that the Hybrid QEAD model achieves the highest detection accuracy (91.44%), outperforming Classical DL and Quantum ML in energy efficiency, with statistically significant improvements (ANOVA, p < 0.05). The quantum properties of superposition and entanglement enhance feature representation and parallel computation, resulting in faster and more accurate threat detection. To address current hardware limitations such as circuit depth and quantum noise, the framework explores practical mitigation strategies including zero-noise extrapolation (ZNE), probabilistic error cancellation (PEC), and noise-aware variational circuit training. Despite these constraints, QEAD demonstrates viable deployment potential in prequantum transition infrastructures. The findings establish QEAD as a scalable solution for post-quantum cybersecurity, with future applications in Quantum Blockchain, Federated Quantum Learning, and Quantum IoT Security.