Implementation of a quantum random number generator based on the optimal clustering of photocounts

To implement quantum random number generators, it is fundamentally important to have a mathematically provable and experimentally testable process of measurements of a system from which an initial random sequence is generated. This makes sure that randomness indeed has a quantum nature. A quantum random number generator has been implemented with the use of the detection of quasi-single-photon radiation by a silicon photomultiplier (SiPM) matrix, which makes it possible to reliably reach the Poisson statistics of photocounts. The choice and use of the optimal clustering of photocounts for the initial sequence of photodetection events and a method of extraction of a random sequence of 0’s and 1’s, which is polynomial in the length of the sequence, have made it possible to reach a yield rate of 64 Mbit/s of the output certainly random sequence.     

基于单光子脉冲时间随机性的光量子随机源

提出了一种基于单光子脉冲时间随机性的光量子随机源。利用衰减成单光子态的光强恒定光源和一个单光子探测器产生单光子随机脉冲,通过连续比较单光子随机脉冲序列中相邻两个脉冲的时间间隔来提取随机位。通过设计高速响应的微通道板单光子探测器和基于现场可编程门阵列(FPGA)的随机位提取电路,获得了超过10Mbit/s的随机位产生速率。通过采用恒比定时和对计数时钟倍频的方法提高时间间隔的测量精度,从而减小随机位序列的相关系数。当光量子随机源的随机位产生速率在10kbit/s以下时,所获得的二进制随机位序列的相关系数小于0.001。运用随机性测试程序ENT和DIEHARD对所获的随机位序列进行测试,测试结果表明序列的随机性非常好且不需要后续处理,完全满足真随机数的标准。     

偏振光量子随机源

报道了一种基于偏振光量子的随机效应产生的随机源，这种方法利用了单个偏振光子在偏振分束镜表现出来的量子随机性.用同步符合单光子检测技术，对衰减的偏振单光子源在偏振分束镜表现的随机性进行检测，利用计算机和数据采集卡，获得了二元随机码.利用国际通用的随机数检测程序(ENT)对直接获得的数据进行随机性分析，结果完全满足真随机数的标准.     

基于光子间隙随机分布的真随机数源

提出了利用模数转换器提高真随机数源速率的方案, 该方案基于衰减脉冲激光光子间隙随机分布, 可使随机数的产生速率提高十几倍.实验中将时间幅度转换仪与16位模数转换器相结合, 产生的各比特位随机数序列顺利通过了国际通用的随机数检测程序统计测试标准, 该方案实验装置简单, 增强了系统的抗干扰能力. 关键词： 衰减式单光子源 模数转换 延时符合 随机数检测     

A Quantum Random Number Generator Based on the 100-Mbit/s Poisson Photocount Statistics

A quantum random number generator is experimentally realized. The initial randomness source is a sequence of photocounts from quasi-single-photon radiation detected with a SiPM (Silicon Photo Multiplier) silicon avalanche detector array. The use of a SiPM provides a reliable control of the quantum nature of the Poisson photocount statistics. A special algorithm with nonexponential complexity allows one to extract from the Poisson process all the randomness contained in it, namely, a random uniform sequence of 0 and 1.     

A universal algorithm to generate pseudo-random numbers based on uniform mapping as homeomorphism

A specific uniform map is constructed as a homeomorphism mapping chaotic time series into [0,1] to obtain sequences of standard uniform distribution. With the uniform map, a chaotic orbit and a sequence orbit obtained are topologically equivalent to each other so the map can preserve the most dynamic properties of chaotic systems such as permutation entropy. Based on the uniform map, a universal algorithm to generate pseudo random numbers is proposed and the pseudo random series is tested to follow the standard 0-1 random distribution both theoretically and experimentally. The algorithm is not complex, which does not impose high requirement on computer hard ware and thus computation speed is fast. The method not only extends the parameter spaces but also avoids the drawback of small function space caused by constraints on chaotic maps used to generate pseudo random numbers. The algorithm can be applied to any chaotic system and can produce pseudo random sequence of high quality, thus can be a good universal pseudo random number generator.     

基于光量子的真随机源

介绍基于单光子的量子随机性产生二元真随机序列的实验以及所采用的数学处理方法.实验利用单光子探测器,较高速的信号处理电路和计算机数据采集系统,接收记录随机选择反射或折射路径通过50/50分束器的光子,从而获得原始的二元随机序列.用Huffman编码方法把原始数据压缩为符合密码学要求的真随机序列.随机序列采集的速率理论上可达200kbit/s. 关键词： 真随机数源 单光子 光子束器 Huffman编码及数据压缩     

True Random Number Generator Realized by Extracting Entropy from a Negative-Inductance Superconducting Quantum Interference Device

A new type of superconductive true random number generator(TRNG) based on a negative-inductance superconducting quantum interference device(nSQUID) is proposed. The entropy harnessed to generate random numbers comes from the phenomenon of symmetry breaking in the nSQUID. The experimental circuit is fabricated by the Nb-based lift-off process. Low-temperature tests of the circuit verify the basic function of the proposed TRNG.The frequency characteristics of the TRNG have been analyzed by simulation. The generation rate of random numbers is expected to achieve hundreds of megahertz to tens of gigahertz.     

基于广义信息域离散轨迹变换的随机数生成器

广义信息域是所有可表示为二进制编码的数字信息构成的空间. 本文提出一种基于广义信息域离散轨迹变换的随机数生成器. 该生成器将广义信息域作为熵源空间, 把用户选择的数字信息作为熵源输出, 在对熵源输出进行重构处理的基础上使用离散轨迹变换方法生成随机数. 本文提出的生成器在平衡度、周期和抗碰撞等性能上均表现优良, 并通过美国国家标准技术研究院 测试证明其具有理想的随机性, 可以供用户快速方便地生成高安全随机数.     

A hybrid-type quantum random number generator

This paper proposes a well-performing hybrid-type truly quantum random number generator based on the time interval between two independent single-photon detection signals, which is practical and intuitive, and generates the initial random number sources from a combination of multiple existing random number sources. A time-to-amplitude converter and multichannel analyzer are used for qualitative analysis to demonstrate that each and every step is random. Furthermore, a carefully designed data acquisition system is used to obtain a high-quality random sequence. Our scheme is simple and proves that the random number bit rate can be dramatically increased to satisfy practical requirements.     

物理真随机码发生器随机性分析

对物理随机码发生器的物理参量与其产生的随机码序列的随机性关系进行了分析.根据量子保密通信对随机码序列的随机性的要求，分析了常见的随机码发生器产生的随机码的随机性，给出了利用随机高斯噪音经比较器产生随机码的随机码发生器的随机性公式.     

Slow Modes in Passive Advection

The anomalous scaling in the Kraichnan model of advection of the passive scalar by a random velocity field with nonsmooth spatial behavior is traced to the presence of slow resonance-type collective modes of the stochastic evolution of fluid trajectories. We show that the slow modes are organized into infinite multiplets of descendants of the primary conserved modes. Their presence is linked to the nondeterministic behavior of the Lagrangian trajectories at high Reynolds numbers caused by the sensitive dependence on initial conditions within the viscous range where the velocity fields are more regular. Revisiting the Kraichnan model with smooth velocities, we describe the explicit solution for the stationary state of the scalar. The properties of the probability distribution function of the smeared scalar in this state are related to a quantum mechanical problem involving the Calogero–Sutherland Hamiltonian with a potential.Partially supported by NSF Grant DMS-9205296     

Physical generation of random numbers using an asymmetrical Boolean network

Autonomous Boolean networks (ABNs) have been successfully applied to the generation of random number due to their complex nonlinear dynamics and convenient on-chip integration. Most of the ABNs used for random number generators show a symmetric topology, despite their oscillations dependent on the inconsistency of time delays along links. To address this issue, we suggest an asymmetrical autonomous Boolean network (aABN) and show numerically that it provides large amplitude oscillations by using equal time delays along links and the same logical gates. Experimental results show that the chaotic features of aABN are comparable to those of symmetric ABNs despite their being made of fewer nodes. Finally, we put forward a random number generator based on aABN and show that it generates the random numbers passing the NIST test suite at 100 Mbits/s. The unpredictability of the random numbers is analyzed by restarting the random number generator repeatedly. The aABN may replace symmetrical ABNs in many applications using fewer nodes and, in turn, reducing power consumption.     

Implementation and comparative study of random sequences for nonlinear least square data fitting

A numerical study of nonlinear least square data fitting using random numbers from the congruential generator and several quasi-random generators is presented. The results indicate that at least up to five dimensions some of the quasi-random sequences yield better accuracy than the congruential pseudo-random sequence. Some recommendations for selecting the generators of quasi-random sequences are also given.     

Image encryption using random sequence generated from generalized information domain

A novel image encryption method based on the random sequence generated from the generalized information domain and permutation–diffusion architecture is proposed. The random sequence is generated by reconstruction from the generalized information file and discrete trajectory extraction from the data stream. The trajectory address sequence is used to generate a P-box to shuffle the plain image while random sequences are treated as keystreams. A new factor called drift factor is employed to accelerate and enhance the performance of the random sequence generator. An initial value is introduced to make the encryption method an approximately one-time pad. Experimental results show that the random sequences pass the NIST statistical test with a high ratio and extensive analysis demonstrates that the new encryption scheme has superior security.     

基于数模混合的混沌映射实现

混沌随机序列发生器在数字实现时面临有限字长效应, 无法严格保证伪随机序列的非周期性. 构建了一类包含最少模拟器件的新数模混合系统, 分析比较了此类系统的非线性动力学行为. 利用现场可编程逻辑门阵列和RC电路实现了混沌映射, 构造了稳定的高速随机序列发生器, 可产生100 Gbit/s以上速率的随机数. 研究表明, 数模混合系统的混沌性对元件参数变化不敏感, 数模实现验证了新系统的存在性和物理上的可实现性. 系统易于集成在数字加密、保密通信和雷达波形产生等应用系统中.     

利用混沌激光多位量化实时产生14 Gb/s的物理随机数

提出了一种基于混沌激光多位量化的高速物理随机数实时产生方法.利用外腔反馈混沌半导体激光器作为物理熵源,通过时钟速率为7 GHz的多位模数转换器对其采样量化,生成6位有效位的二进制随机比特,然后利用现场可编程软件抽取低2位有效位的随机序列并进行自延迟异或处理,获得了实时速率为14 Gb/s的物理随机数.该随机数具有良好的统计随机性,可成功通过随机数行业测试标准(NIST SP 800-22).     

Consideration for Affects of an XOR in a Random Number Generator Using Ring Oscillators

A cloud service to offer entropy has been paid much attention to. As one of the entropy sources, a physical random number generator is used as a true random number generator, relying on its irreproducibility. This paper focuses on a physical random number generator using a field-programmable gate array as an entropy source by employing ring oscillator circuits as a representative true random number generator. This paper investigates the effects of an XOR gate in the oscillation circuit by observing the output signal period. It aims to reveal the relationship between inputs and the output through the XOR gate in the target generator. The authors conduct two experiments to consider the relevance. It is confirmed that combining two ring oscillators with an XOR gate increases the complexity of the output cycle. In addition, verification using state transitions showed that the probability of the state transitions was evenly distributed by increasing the number of ring oscillator circuits.     

Entanglement and Classical Correlations in the Quantum Frame

The frame of classical probability theory can be generalized by enlarging the usual family of random variables in order to encompass nondeterministic ones. This leads to a frame in which two kinds of correlations emerge: the classical correlation that is coded in the mixed state of the physical system and a new correlation, to be called probabilistic entanglement, which may occur also at pure states. We examine to what extent this characterization of correlations can be applied to quantum mechanics. Explicit calculations on simple examples outline that a same quantum state can show only classical correlations or only entanglement depending on its statistical content; situations may also arise in which the two kinds of correlations compensate each other.     

Statistics of states generated by quantum-scissors device

Generating desired states is a prerequisite in quantum information. Some desired states can be generated by a quantum-scissors device(QSD). We present a detailed analysis of the properties of the generated states, including average photon numbers and intensity gains. The theoretical analysis shows that there is a nondeterministic amplification in terms of the average photon number under the condition that the average photon number of the input state is less than 1. In contrast to the input states, the generated states show the nonclassical property described by the negativity of the Wigner function. Furthermore, we generalize the QSD to truncate arbitrary photon number terms of the input states, which may be useful in high-dimensional quantum information processing.