213 research outputs found
The avalanche dynamics in Bak-Sneppen evolution model observed with standard distribution width of fitness
See the updated version arXiv:nlin/0111028.Comment: This paper has been withdrawn by the author due to a updated version
was submitte
Implementation for Solving Random Satisfiability Problems through CNOT-based circuits in a NMR Quantum Processor
We give a general method of construting quantum circuit for random
\QTR{it}{satisfiability} (SAT) problems with the basic logic gates such as
multi-qubit controlled-NOT and NOT gates. The sizes of these circuits are
almost the same as the sizes of the SAT formulas. Further, a parallelization
scheme is described to solve random SAT problems efficiently through these
quantum circuits in \QTR{it}{nuclear magnetic resonance} (NMR) ensemble quantum
computing. This scheme exploits truly mixed states as input states rather than
pseudo-pure states, and combines with the topological nanture of the NMR
spectrum to identify the solutions to SAT problems in a parallel way. Several
typical SAT problems have been experimentally demonstrated by this scheme with
good performances.Comment: 17 pages, 7 figure
Experimental demonstration of the interferometric complementarity of one- and two-particle interference in a bulk Nuclear Magnetic Resonance ensemble
We analyze an interferometric complementarity between one- and two-particle
interference in the general case: , ,
and further examine the relation among one-particle interference visibility
, two-particle interference visibility and the predication
of the path of a single particle. An equality
, is achieved for any pure
two-particle source, which implies the condition of the complementarity
relation to reach the upper bound and its relation to another interferometric
complementarity between path information and interference visibility of a
single particle. Meanwhile, the relationships of the complementarities and the
entanglement of the composite system are also investigated. Using nuclear
magnetic resonance techniques, the two-particle interferometric complementarity
was experimentally tested with the ensemble-averaged spin states, including two
extreme cases and an intermediate case.Comment: 8 pages, 4 PS figure
Nuclear Magnetic Resonance Implemenations of Remote State Preparation of Arbitary Longitudinal Qubit and Remote State Measurement of a Qubit
A qubit chosen from equatorial or polar great circles on a Bloch sphere can
be remotely prepared with an Einstain-Podolsky-Rosen (EPR) state shared and a
cbit communication. We generalize this protocal into an arbitrary longitudinal
qubit on the Bloch sphere in which the azimuthal angle phi can be an arbitrary
value instead of only being zero. The generalized scheme was experimentally
realized using liquid-state nuclear magnetic resonance (NMR) techniques. Also,
we have experimentally demonstrated remote state measurement (RSM) on an
arbitary qubit proposed by Pati.Comment: 10 pages, 3 PS figure
Quantum computing by pairing trapped ultracold ions
The superpositional wave function oscillations for finite-time implementation
of quantum algorithms modifies the desired interference required for quantum
computing. We propose a scheme with trapped ultracold ion-pairs being qubits to
diminish the detrimental effect of the wave function oscillations, and apply
the scheme to the two-qubit Grover's search. It can be also found that the
qubits in our scheme are more robust against the decoherence caused by the
environment, and the model is scalable.Comment: 10 pages, no figure
Comparison and Benchmarking of AI Models and Frameworks on Mobile Devices
Due to increasing amounts of data and compute resources, deep learning
achieves many successes in various domains. The application of deep learning on
the mobile and embedded devices is taken more and more attentions, benchmarking
and ranking the AI abilities of mobile and embedded devices becomes an urgent
problem to be solved. Considering the model diversity and framework diversity,
we propose a benchmark suite, AIoTBench, which focuses on the evaluation of the
inference abilities of mobile and embedded devices. AIoTBench covers three
typical heavy-weight networks: ResNet50, InceptionV3, DenseNet121, as well as
three light-weight networks: SqueezeNet, MobileNetV2, MnasNet. Each network is
implemented by three frameworks which are designed for mobile and embedded
devices: Tensorflow Lite, Caffe2, Pytorch Mobile. To compare and rank the AI
capabilities of the devices, we propose two unified metrics as the AI scores:
Valid Images Per Second (VIPS) and Valid FLOPs Per Second (VOPS). Currently, we
have compared and ranked 5 mobile devices using our benchmark. This list will
be extended and updated soon after
Analytical energy spectrum for hybrid mechanical systems
We investigate the energy spectrum for hybrid mechanical systems described by
non-parity-symmetric quantum Rabi models. A set of analytical solutions in
terms of the confluent Heun functions and their analytical energy spectrum are
obtained. The analytical energy spectrum includes regular and exceptional
parts, which are both confirmed by direct numerical simulation. The regular
part is determined by the zeros of the Wronskian for a pair of analytical
solutions. The exceptional part is relevant to the isolated exact solutions and
its energy eigenvalues are obtained by analyzing the truncation conditions for
the confluent Heun functions. By analyzing the energy eigenvalues for
exceptional points, we obtain the analytical conditions for the
energy-level-crossings, which correspond to two-fold energy degeneracy.Comment: 17 pages, 2 figure
Exhibition of the periodicity of Quantum Fourier Transformation in Nuclear Magnetic Resonance
The remarkable capability of quantum Fourier transformation (QFT) to extract
the periodicity of a given periodic function has been exhibited by using
nuclear magnetic resonance (NMR) techniques. Two separate sets of experiments
were performed. In a full QFT, the periodicity were validated with state
tomography and fidelity measurements. For a simplified QFT, the three-qubit
pseudo-pure state was created by introducting an additional observer spin, and
the spectra recorded on the observer spin showed intuitively the power of QFT\
to find the periodicity. Experimentally realizing the QFT provides a critical
step to implement the renowned Shor's quantum factoring algorithm and many
other algorithms. Moveover, it can be applied to the study of quantum chaos and
other quantum information processing.Comment: 12 pages, 3 tables and 4 PS figure
Chaotic atomic population oscillations between two coupled Bose-Einstein condensates with time-dependent asymmetric trap potential
We have investigated the chaotic atomic population oscillations between two
coupled Bose-Einstein condensates (BEC) with time-dependent asymmetric trap
potential. In the perturbative regime, the population oscillations can be
described by the Duffing equation, and the chaotic oscillations near the
separatrix solution are analyzed. The sufficient-necessary conditions for
stable oscillations depend on the physical parameters and initial conditions
sensitively. The first-order necessary condition indicates that the Melnikov
function is equal to zero, so the stable oscillations are Melnikov chaotic. For
the ordinary parameters and initial conditions, the chaotic dynamics is
simulated with numerical calculation. If the damping is absent, with the
increasing of the trap asymmetry, the regular oscillations become chaotic
gradually, the corresponding stroboscopic Poincare sections (SPS) vary from a
single island to more islands, and then the chaotic sea. For the completely
chaotic oscillations, the long-term localization disappears and the short-term
localization can be changed from one of the BECs to the other through the route
of Rabi oscillation. When there exists damping, the stationary chaos
disappears, the transient chaos is a common phenomenon before regular stable
frequency locked oscillations. And proper damping can keep localization
long-lived.Comment: Retex, 20 Pages, 9 PS figure
Identifying Dwarfs Workloads in Big Data Analytics
Big data benchmarking is particularly important and provides applicable
yardsticks for evaluating booming big data systems. However, wide coverage and
great complexity of big data computing impose big challenges on big data
benchmarking. How can we construct a benchmark suite using a minimum set of
units of computation to represent diversity of big data analytics workloads?
Big data dwarfs are abstractions of extracting frequently appearing operations
in big data computing. One dwarf represents one unit of computation, and big
data workloads are decomposed into one or more dwarfs. Furthermore, dwarfs
workloads rather than vast real workloads are more cost-efficient and
representative to evaluate big data systems. In this paper, we extensively
investigate six most important or emerging application domains i.e. search
engine, social network, e-commerce, multimedia, bioinformatics and astronomy.
After analyzing forty representative algorithms, we single out eight dwarfs
workloads in big data analytics other than OLAP, which are linear algebra,
sampling, logic operations, transform operations, set operations, graph
operations, statistic operations and sort
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