Asymmetrical Quantum Encryption Protocol Based on Quantum Search Algorithm

Chuyue Pan, Tao Shang, Jianwei Liu

Wenjun Luo, Guanli Liu

Quantum cryptography and quantum search algorithm are considered as two important research topics in quantum information science. An asymmetrical quantum encryption protocol based on the properties of quantum one-way function and quantum search algorithm is proposed. Depending on the no-cloning theorem and trapdoor one-way functions of the public-key, the eavesdropper cannot extract any private-information from the public-keys and the ciphertext. Introducing key-generation randomized logarithm to improve security of our proposed protocol, i.e., one private-key corresponds to an exponential number of public-keys. Using unitary operations and the single photon measurement, secret messages can be directly sent from the sender to the receiver. The security of the proposed protocol is proved that it is information-theoretically secure. Furthermore, compared the symmetrical Quantum key distribution, the proposed protocol is not only efficient to reduce additional communication, but also easier to carry out in practice, because no entangled photons and complex operations are required.

Shi-Jin Zhong, Jin-Huan Li, Ying-Nan Zhao +2 more

Abstract The quantum asymmetric key encryption (QAKE) is a prominent research frontier in quantum information. In this paper, we propose a quantum asymmetric key encryption scheme based on the exact quantum search algorithm (QAKE-EQSA). Leveraging EQSA’s deterministic amplitude amplification and a unique three-oracle structure, comprising an auxiliary oracle, its inverse, and a message-dependent oracle, the proposed QAKE-EQSA scheme guarantees a 100% decryption success rate. Within the scheme, the public key is generated by applying the auxiliary oracle to a specific quantum superposition state and subsequently shared via a public key center; the private key is constructed using a phase-matching diffusion operator; and the message is encoded into a unique target state within the search space, ensuring that only the legitimate receiver can recover it exactly. Furthermore, we demonstrate a 4-qubit instantiation of the QAKE-EQSA scheme on the MindQuantum platform and conduct a comprehensive analysis encompassing its security, qubit efficiency, and practical performance. Our analysis demonstrates that, in comparison to several existing QPKE schemes, the proposed QAKE-EQSA scheme achieves exact decryption, optimal qubit efficiency, and enhanced resistance against quantum attacks.

Tao Shang

Wenjing Li, Qinghai Ou, Hongfa Li +4 more

Here, The new arbitrated quantum signature (AQS) protocol assisted by asymmetric key based on qubit block encryption algorithm is given. Interestingly, our protocol with the asymmetric key can be easily extended to multi-party verification. Unlike all previous quantum works on arbitrated quantum signature, the encryption algorithm of the pre-sented protocol is qubit block encryption. Since, the proposed protocol has a better performance in resisting existential forgery attack. In addi-tion, with the help of the arbitrator, it can be proved that our protocol is secure.

Xi Huang, Shibin Zhang, Yan Zuo Chang +3 more