Chong-Qiang Ye

Quantum private set computation plays a crucial role in secure multi-party computation and privacy-preserving data mining. However, in quantum resource-constrained scenarios, most existing semi-quantum private set computation protocols rely on entangled states, making them difficult to scale effectively to multi-party settings. To address these limitations, this paper proposes a semi-quantum protocol for private set intersection and union cardinality computation. The proposed protocol uses single-particle states as information carriers and establishes the required keys by exploiting the correlations between prepared quantum states and selected measurement bases, thus avoiding the need for entangled states and pre-shared keys. By adopting a star topology, the protocol is further extended to general multiparty scenarios, with resource costs increasing linearly rather than exponentially. Security and performance analyses show that the proposed protocol can resist typical external and internal attacks. Compared with existing protocols, it reduces quantum resource requirements while achieving advantages in qubit efficiency and scalability.

Quantum entanglement is a fundamental resource in quantum information science. In recent years, many researchers have explored the use of machine learning techniques to detect entanglement. However, most existing models still suffer from limited classification and generalization capability. To address these issues, we construct a randomly generated dataset of three‐qubit quantum states covering fully separable, bi‐separable, and genuine entangled states, and train a complex‐valued convolutional neural network to classify these three classes. Numerical results demonstrate that the proposed model accurately identifies all separability classes and exhibits strong generalization performance not only on the constructed dataset but also on various noisy quantum states, including noisy GHZ, W, GHZ‐W mixed, and hypergraph states, achieving an overall accuracy of 98.6%. In addition, we test the ability of the proposed model to identify certain positive‐partial‐transpose entangled states (PPTES), as well as quantum states that undergo local unitary (LU) operations. All of these results indicate that the proposed model can accurately identify the separability of most three‐qubit quantum states and can also serve as a reliable tool, providing highly probable and accurate predictions when theoretical methods fail.

With the rapid development of IoT technology, securely querying sensitive data collected by devices within a specific range has become a focal concern for users. This paper proposes a privacy-preserving range query scheme based on quantum encryption, along with circuit simulations and performance analysis. We first propose a quantum private set similarity comparison protocol and then construct a privacy-preserving range query scheme for IoT environments. By leveraging the properties of quantum homomorphic encryption, the proposed scheme enables encrypted data comparisons, effectively preventing the leakage of sensitive data. The correctness and security analysis demonstrates that the designed protocol guarantees users receive the correct query results while resisting both external and internal attacks. Moreover, the protocol requires only simple quantum states and operations, and does not require users to bear the cost of complex quantum resources, making it feasible under current technological conditions.

Semi-quantum private comparison allows multiple ‘classical’ users who have restricted quantum capabilities to compare their private data with the assistance of a quantum third party. In this work, we propose a novel dynamic semi-quantum private comparison protocol using a circular transmission mode along with d-dimensional single-particle states. The protocol enables the comparison of data size relations among several ‘classical’ users, while the third party can only determine the relative sizes without accessing the users’ secret information. Security evaluations demonstrate that the designed protocol withstands typical external and internal attacks. Compared to previous works, this protocol offers several improvements: first, it supports dynamic addition or removal of users, enhancing applicability in practical scenarios; second, it eliminates the need for pre-shared keys, reducing quantum resource consumption; third, it avoids the use of high-dimensional multi-particle entangled states, thereby enhancing the feasibility of implementation. Therefore, the proposed protocol may have more practical potential compared to previous protocols.

Semi-quantum secret sharing facilitates the sharing of private data between quantum users and ‘classical’ users with limited quantum capabilities, thereby lowering the barrier to utilizing quantum technology. However, most current semi-quantum secret sharing protocols are confined to ideal environments and two-party scenarios. In this paper, we design two collective noise-resistant multi-party semi-quantum secret sharing protocols based on decoherence-free states to address potential noise interference during transmission. These protocols use decoherence-free states as information carriers for data interaction and exhibit strong resilience to both internal and external threats. We also conduct simulation experiments using IBM Qiskit to verify the stability and feasibility of the protocols in the noisy environments. The results of these experiments underscore the robustness of the protocols, particularly in the presence of collective noise. Compared with previous related protocols, our protocols have advantages in noise resistance and applicability to multi-party scenarios. Therefore, the proposed protocols may be more in line with the secret sharing needs of actual environments.

Semi-quantum secret sharing (SQSS) protocols serve as fundamental frameworks in quantum secure multi-party computations, offering the advantage of not requiring all users to possess intricate quantum devices. However, the current landscape of SQSS protocols predominantly caters to bipartite scenarios, rendering them inadequate for practical multi-party secret sharing requirements. Addressing this gap, this paper proposes a novel SQSS protocol based on multi-particle GHZ states. In this protocol, the quantum user distributes predetermined secret information to multiple classical users with limited quantum capabilities, necessitating collaborative efforts among all classical users to reconstruct the correct secret information. By utilizing measure-flip and reflect operations, the transmitted multi-particle GHZ states can all contribute keys, thereby improving the utilization of transmitted particles. Security analysis shows that the protocol's resilience against prevalent external and internal threats. Additionally, employing IBM Qiskit, we conduct quantum circuit simulations to validate the protocol's accuracy and feasibility. Compared with similar studies, the proposed protocol has advantages in terms of protocol scalability, qubit efficiency, and shared message types.

Semi‐quantum secure summation allows multiple parties with limited quantum capabilities to perform collective calculations under the premise of protecting privacy. However, current approaches are confined to low‐dimensional quantum states as information carriers and are restricted to scenarios involving two or three parties. This limitation hinders their universality and ability to fulfill the requirements of practical secure multiparty computations. To address these challenges, a novel semi‐quantum secure multiparty summation (SQSMS) protocol is proposed based on high‐dimensional entangled states and single‐particle states. The protocol leverages the entanglement correlation to guarantee the security of the transmission, enabling resistance against various potential attacks. Then, by utilizing the IBM Qiskit platform, corresponding quantum circuits and simulation results are presented to validate the feasibility and correctness of the protocol. Furthermore, building upon the foundation of the SQSMS protocol, semi‐quantum anonymous auction and anonymous ranking protocols are further constructed. Compared with previous approaches, the designed protocols cater to the requirements of their respective counterparts. Consequently, the approach may have broad applications in semi‐quantum secure multiparty computation scenarios.

Privacy comparison is an important research topic in secure multi-party computing, widely used in e-commerce, secret ballots, and other fields. However, the development of quantum computing power poses a growing potential security threat to secure multi-party algorithms based on mathematically tricky problems, and most of the proposed quantum privacy comparison schemes could be more efficient. Therefore, based on the W-state, we offer a more efficient semi-quantum privacy comparison method. The security analysis shows that the scheme can resist third-party, measurement, and entanglement attacks. Compared with the previous work, the scheme significantly improves communication efficiency and has stronger practicability.