arXiv subjects

Yu-Guang Yang

Publications and source records attributed to Yu-Guang Yang.

9 recordsLinked to original sources

arXiv2026

Local distinguishability of five five-partite orthogonal product states

The local distinguishability of five orthogonal product states (OPSs) has been studied in several multipartite settings, but the five-partite case still requires a systematic characterization. In this paper, we consider five five-partite OPSs, where any two states are orthogonal on exactly one subsystem. By analyzing the distribution of ten pairwise orthogonality relations over five subsystems, we classify the corresponding orthogonality structures by colored orthogonality graphs. After eliminating identical graphs under relabeling of states and permutation of subsystems, we obtain 443 different graphs in seven genuinely five-partite categories. We prove that the OPSs corresponding to 434 of these graphs can be perfectly distinguished by local operations and classical communication (LOCC), while the remaining 9 exceptional cases fall into two types and require separate analysis. Our results give a characterization of the local distinguishability of five OPSs in five-partite OPSs.

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arXiv2026

Local distinguishability of five quadripartite orthogonal product states

The local distinguishability of five bipartite and tripartite orthogonal product states (OPSs) has been effectively resolved, while that of five quadripartite OPSs has not yet been effectively addressed. In this paper, we give the local distinguishability of five quadripartite OPSs, where any two of these five states are orthogonal on exactly one subsystem. Based on the vectors of the numbers of pairwise orthogonality relations, we classify different sets of five quadripartite OPSs into nine categories, which correspond to 371 distinct orthogonality graphs. We show that the sets of five quadripartite OPSs corresponding to 355 of the 371 cases can be perfectly distinguished by local operations and classical communication (LOCC), whereas the sets of five quadripartite OPSs for the remaining 16 cases cannot exactly distinguished by LOCC. Our results enrich the theory of nonlocality for sets of OPSs.

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arXiv2026

A self-tallying quantum anonymous voting protocol for multiple-selection elections

Self-tallying quantum anonymous voting (SQAV) has drawn considerable attention since it was proposed. However, constrained by design challenges, all existing protocols only accommodate single-selection voting and cannot support multi-selection voting. In this paper, we propose a SQAV protocol with multi-selection voting functionality. In our protocol, $nm$ $n$-particle entangled states are equally divided into $n$ groups, and the $n$ particles in each entangled state are delivered to $n$ voters, one particle per voter. Each voter obtains $n$ voting vectors by sequentially measuring all his (or her) particles that belong to $n$ different group, and then encodes his or her voting information into the vector corresponding to the secret index. Due to entanglement correlation, each voter can verify whether his or her ballot is correct through computation, while any participant can obtain the vote count for each candidate through computation. Our protocol satisfies self-tallying, nonreusability, verifiability, and fairness.

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arXiv2026

Construction of Sets of Orthogonal Quantum States with Minimal Nonlocality in Bipartite and Tripartite Systems of Unequal Local Dimensions

The research on minimal nonlocality aims to determine the minimal cardinality of nonlocal sets of quantum states. However, the construction of a nonlocal set of states in bipartite or tripartite quantum systems with unequal local dimensions remains unsolved. In this paper, we first give a method to construct a set of orthogonal quantum states with minimal nonlocality in $\mathbb{C}^{4} \otimes \mathbb{C}^{7}$ quantum system. Then we give a general method to construct a set of orthogonal quantum states with minimal nonlocality in a bipartite quantum system with unequal local dimensions. Furthermore, we generalize the construction method to tripartite quantum system with unequal local dimensions, and construct a set of orthogonal quantum states with minimal nonlocality in $\mathbb C^{d_1} \otimes \mathbb C^{d_2}\otimes \mathbb C^{d_3}$ quantum system for $5\le d_1 < d_2 < d_3$. Our work settles the construction problem of a set of orthogonal states with minimal nonlocality in both bipartite and tripartite systems with unequal local dimensions.

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arXiv2026

Local distinguishability of six bipartite orthogonal product states

It is necessary to investigate the local distinguishability of orthogonal quantum state sets, as their adoption in protocol design helps diminish quantum state transmission and cut operational costs. In this paper, we explore the local distinguishability of six orthogonal product states (OPSs) on any bipartite quantum system. We classify different sets of six bipartite OPSs into eight categories by using the vectors of the numbers of pairwise orthogonality relations, where any two states are orthogonal on only one subsystem within each set. We find that these eight categories contain a total of 78 distinct cases, all but five of which are perfectly distinguishable via local operations and classical communication (LOCC). Furthermore, we discuss the local distinguishability of those five distinct cases in detail. Our work explicitly characterizes the local distinguishability of six bipartite OPSs.

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arXiv2026

Local distinguishability of five orthogonal product states on bipartite and tripartite quantum systems

Local distinguishability of orthogonal quantum states can effectively reduce the consumption of quantum resources and lower economic costs in quantum protocols. Although numerous achievements have been made regarding local distinguishability of orthogonal quantum states, some fundamental issues have not been effectively addressed. For example, the local distinguishability of five orthogonal product states (OPSs) is still unknown up to now. In this paper, we give the properties of local distinguishability of five OPSs on bipartite and tripartite quantum systems. Firstly, to characterize the structure of a set of bipartite OPSs, we propose the concept of the vector of orthogonal relations for a set of bipartite OPSs. Secondly, we classify the structures of five bipartite OPSs into six categories by this concept and prove that five of these six categories can be perfectly distinguished by local operations and classical communication (LOCC). Thirdly we show that the local distinguishability of each case of the sixth category singly. On the other hand, we first divide the structures of five tripartite OPSs into eight categories by the vectors of orthogonal relations of five tripartite OPSs. Then we give the local distinguishability of each category. Our work enriches the research results of quantum nonlocality and will provide a clear understanding of the local distinguishability of five OPSs.

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arXiv2023

A high-fidelity quantum state transfer algorithm on the complete bipartite graph

High-fidelity quantum state transfer is critical for quantum communication and scalable quantum computation. Current quantum state transfer algorithms on the complete bipartite graph, which are based on discrete-time quantum walk search algorithms, suffer from low fidelity in some cases. To solve this problem, in this paper we propose a two-stage quantum state transfer algorithm on the complete bipartite graph. The algorithm is achieved by the generalized Grover walk with one marked vertex. The generalized Grover walk's coin operators and the query oracles are both parametric unitary matrices, which are designed flexibly based on the positions of the sender and receiver and the size of the complete bipartite graph. We prove that the fidelity of the algorithm is greater than $1-2ε_{1}-ε_{2}-2\sqrt{2}\sqrt{ε_{1}ε_{2}}$ or $1-(2+2\sqrt{2})ε_{1}-ε_{2}-(2+2\sqrt{2})\sqrt{ε_{1}ε_{2}}$ for any adjustable parameters $ε_{1}$ and $ε_{2}$ when the sender and receiver are in the same partition or different partitions of the complete bipartite graph. The algorithm provides a novel approach to achieve high-fidelity quantum state transfer on the complete bipartite graph in any case, which will offer potential applications for quantum information processing.

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arXiv2019

Szegedy Quantum Walks with Memory on Regular Graphs

Quantum walks with memory(QWM) are a type of modified quantum walks that record the walker's latest path. The general model of coined QWM is presented in Phys. Rev. A 93, 042323 (2016). In this paper, we present general model of Szegedy QWM. Importantly, the relation of coined QWM and Szegedy QWM is revealed. By transforming coined QWM to Szegedy QWM, some amazing results about QWM are founded.

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arXiv2017

Controlled Alternate Quantum Walks based Quantum Hash Function

Through introducing controlled alternative quantum walks, we present controlled alternate quantum walks (CAQW) based quantum hash function. CAQW based quantum hash function have excellent security, outstanding statistical performance and splendid expansibility. Furthermore, due to the structure of alternative quantum walks, implementing CAQW based quantum hash function significantly reduces the resources necessary for its feasible experimental realization than implementing other quantum hash functions. Besides, CAQW based quantum hash function has expansibility.

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