Optical quantum router with cross-phase modulation

The quantum router is a key part of a quantum network. How to design a fully quantum router is a dominant theme in the area of quantum communication. Based on the cross-phase modulation technique, we propose a scheme to realize an optical quantum router using the c-path operation for its basic operation. This router is a perfect, fully quantum router, and it is available for arbitrary （separated or entangled） input signals and covers all possible control modes （the general n-control-m mode）. Moreover, this router protects target signals and preserves quantum features, such as coherent superposition and entanglement. This is a new and powerful feature when compared with classical routers. With the development of current experimental technology, our scheme is feasible.     

量子隐形传态原理及其MATLAB仿真

由于没有操纵量子比特的条件,MATLAB成为通信工程人员和在校学生学习量子通信基本原理的良好工具。文章给出了量子隐形传态的概念,分析了量子隐形传态原理。编写了量子隐形传态的仿真程序。给出了量子交换机仿真程序的核心部分代码。     

Parallelization of a fuzzy control algorithm using quantum computation

Quantum computation is proposed for the parallelization of a fuzzy logic control (FLC) algorithm. Quantum computation speeds up the fuzzy inference since serial operations between matrices of large dimensionality are now replaced by a one-step quantum addition or a quantum subtraction. The unitarity properties of the algorithm prove that the FLC stands for a simulator of a quantum computing machine.     

Qubit mapping of one-way quantum computation patterns onto 2D nearest-neighbor architectures

Quantum Information Processing - The pairwise nonclassical correlations for two-qubit states, extracted from multi-qubit system with exchange symmetry and parity, are quantified by local quantum...     

Uncertainty-like relations of the relative entropy of coherence

Quantum Information Processing - Quantum coherence is an important physical resource in quantum computation and quantum information processing. In this paper, we firstly obtain an uncertainty-like...     

量子遗传算法在TSP中的应用

本文提出了一种改进的量子遗传算法,其核心是对量子遗传算法中的量子旋转门的调整策略进行改进。在现有的静态、指数型动态调整策略的基础上提出了基于正弦函数的动态调整策略。文中对旅行商问题（TSP）的仿真实验结果表明：改进后的算法的优化质量和效率都优于遗传算法和一般量子遗传算法。     

Analytical expression of quantum discord for rank-2 two-qubit states

Quantum correlations characterized by quantum entanglement and quantum discord play important roles in many quantum information processing. We study the relations among the entanglement of formation, concurrence, tangle, linear entropy-based classical correlation and von Neumann entropy-based classical correlation . We present analytical formulae of linear entropy-based classical correlation for arbitrary \(d\otimes 2\) quantum states and von Neumann entropy-based classical correlation for arbitrary \(2\otimes 2\) rank-2 quantum states. From the von Neumann entropy-based classical correlation, we derive an explicit formula of quantum discord for arbitrary rank-2 two-qubit quantum states.     

量子计算的表象无关性探讨

大因数分解和数据检索量子算法的提出带来了量子计算与量子信息的研究高潮。由于量子计算具有并行性、不可克隆性及量子态的不可测性,使得量子信息及量子计算在某些方面具有传统计算所无法比拟的优势。量子的态空间作为一个完备的Hilbert空间,在定义了内积和范数并赋予相应的物理意义后,就构成了理论意义上的量子计算系统。该文抽象了量子系统的本质,描述了量子计算及遵循的计算规则以及如何实现量子信息表示和进行信息的处理与测量,从理论上阐述了量子态系统迁移的线性同构和等距同构,说明了量子计算与量子信息的研究与具体的量子表象空间无关。     

Effect of quantum noise on deterministic joint remote state preparation of a qubit state via a GHZ channel

Quantum Information Processing - Quantum secure communication brings a new direction for information security. As an important component of quantum secure communication, deterministic joint remote...     

量子Daubechies-D（4）小波变换算法及应用研究

由于量子计算相比经典计算具有突出的优越性,设计基于通用量子语言Q_language的量子Daubechies-D（4）小波变换算法对于小波变换的应用和量子算法的完善具有重要的意义。文章分析了Daubechies-D（4）小波变换过程,给出了量子Daubechies-D（4）小波变换算法的Q_language语言描述,并分析得出其时间和空间复杂度,给出了实现量子Daubechies-D（4）小波变换应用方法。     

NEQR量子图像下的差分扩展可逆数据隐藏算法

量子图像安全处理是一个新兴的研究领域,而量子图像数据隐藏是量子图像安全处理技术的一种,在不损害载体的情况下可用于保护量子图像的版权和认证量子图像是否完整。目前尚缺乏对量子图像可逆数据隐藏的详细技术研究。结合差值扩展技术,本文提出了一种量子图像可逆数据隐藏算法：1）选用NEQR量子图像表示法来表示图像;2）借鉴经典的差值扩展算法,在NEQR量子图像上对量子比特进行处理,可逆嵌入数据;3）设计了信息嵌入、信息提取和载体无损恢复的量子线路图,并进行了仿真。基于经典图像的实验结果表明,本文算法是可逆的,可用于将来对量子图像的认证和保护。     

Quantum walks: a comprehensive review

Quantum walks, the quantum mechanical counterpart of classical random walks, is an advanced tool for building quantum algorithms that has been recently shown to constitute a universal model of quantum computation. Quantum walks is now a solid field of research of quantum computation full of exciting open problems for physicists, computer scientists and engineers. In this paper we review theoretical advances on the foundations of both discrete- and continuous-time quantum walks, together with the role that randomness plays in quantum walks, the connections between the mathematical models of coined discrete quantum walks and continuous quantum walks, the quantumness of quantum walks, a summary of papers published on discrete quantum walks and entanglement as well as a succinct review of experimental proposals and realizations of discrete-time quantum walks. Furthermore, we have reviewed several algorithms based on both discrete- and continuous-time quantum walks as well as a most important result: the computational universality of both continuous- and discrete-time quantum walks.     

基于越库配送车辆调度的混合量子遗传算法(QGA)研究

量子遗传算法(QGA)是将经典的量子理论应用到遗传算法当中,将量子态引入传统比特模型中,一种新型的求解最优问题的算法。越库配送车辆调度是一类经典的组合优化问题,基于量子遗传算法,针对提高物流配送过程中要求的快速和高效的问题,本文研究了一种混合量子遗传算法的框架,提出了解决传统物流调度中的配送优化方案的新思路,研究了新的量子更新和概率调整的策略,使该方法更加贴合物流配送的实际问题,实验结果显示,采用混合量子遗传算法后的性能明显优于传统的量子遗传算法,取得了更高的最佳适应度,具有良好的应用前景。     

一种新的量子群进化算法研究

提出了一种基于量子进化的量子群进化算法，使用量子角表示量子比特的状态，并引入改进的粒子群优化策略，对量子群中各量子的量子角进行自适应动态调整．在对0-1背包问题的求解中，表现出很好的性能．     

An overview of quantum cellular automata

Quantum cellular automata are arrays of identical finite-dimensional quantum systems, evolving in discrete-time steps by iterating a unitary operator G. Moreover the global evolution G is required to be causal (it propagates information at a bounded speed) and translation-invariant (it acts everywhere the same). Quantum cellular automata provide a model/architecture for distributed quantum computation. More generally, they encompass most of discrete-space discrete-time quantum theory. We give an overview of their theory, with particular focus on structure results; computability and universality results; and quantum simulation results.

     

Entanglement accessibility measures for the quantum Internet

Quantum Information Processing - We classify the time complexities of three decoding problems for quantum stabilizer codes: quantum bounded distance decoding (QBDD), quantum maximum likelihood...     

Telecloning of qudits via partially entangled states

Quantum Information Processing - We study the process of quantum telecloning of d-dimensional pure quantum states using partially entangled pure states as quantum channel. This process efficiently...     

量子门线路神经网络及其改进学习算法研究

量子门线路神经网络（QGCNN）是一种直接利用量子理论设计神经网络拓扑结构或训练算法的量子神经网络模型。动量更新是在神经网络的权值更新中加入动量,在改变权值向量的同时提供一个特定的惯量,从而避免权值向量在网络训练过程中持续振荡。在基本的量子门线路神经网络的学习算法中引入动量更新原理,提出了一种具有动量更新的量子门线路网络算法（QGCMA）。研究表明,QGCMA保持了网络100%的收敛率,同时,相对于基本算法,在具有相同学习速率的情况下,提高了网络的收敛速度。     

量子计算机实现与展望

量子力学是研究微观粒子特性及其运动规律的物理学分支,它与计算机科学的结合产生了一门新兴学科--量子信息学,即量子计算机.本文先介绍传统计算机的两个发展极限,引出量子计算机的开发背景,再阐述其工作原理和所带来的影响,最后介绍近年来量子计算机的研究成果与其发展前景.     

A novel quantum image steganography algorithm based on exploiting modification direction

Multimedia Tools and Applications - Quantum image steganography is the art and science of hiding secret information into quantum carrier images. This paper proposes a novel quantum image...