Unitary Operator Based Quantum Secure Access Structure for Medical Image Sharing

Ensuring the secure storage and sharing of medical records in the cloud is increasingly crucial due to vulnerabilities in classical encryption methods, such as key manipulation and cloud collusion. This paper introduces a novel quantum-based approach using Quantum Fourier Transform (QFT) and Unitary operators. We designed three quantum circuits for different image sizes: one for the Unitary operator, one for encryption, and one for decryption. DICOM images are first transformed into quantum images with the NEQR algorithm, then encrypted using a Unitary operator, which serves as the encryption key. This key is securely transmitted via quantum teleportation, enhancing protection against classical and quantum attacks. Extensive simulations show the method's effectiveness and robustness in safeguarding medical data during cloud storage and transmission. This makes it a promising solution for secure medical image sharing in quantum communication networks.