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The neutral atoms coupled to a highly excited Rydberg state on a two-dimensional triangular lattice are investigated by employing the density matrix renormalization group technique in the matrix product state form. The full ground-state phase diagram as a function of blockade radius and the detuning of the exciting laser is determined by the behavior of entanglement entropy. We find several quantum phases including stripe-ordered and symmetry-breaking density-wave-ordered phases featured with regular excitation patterns of different excitation densities ρ?=?1/3, 1/4, and 1/7. In addition, a ρ?=?2/3 ordered phase and an interesting “order-by-disorder” phase, which has been prepared experimentally, are also observed in this work. Our work provides an exploration of the possible quantum phases that can occur in a triangularly arrayed Rydberg system, and thus could be a faithful theoretical guide for further experimental research.

We investigate the multipartite entanglement and quantum criticality of neutral atoms on a two-dimensional square lattice, interacting via laser excitation to atom Rydberg states. It is found that the first derivative of residual entanglement with respect to detuning has peaks near the critical point, and corresponding critical behaviors are shown to obey conventional finite-sized scaling, from which we numerically determine the quantum critical point and the critical exponent of the associated correlation length. We also show that there is a sharp peak in the fidelity susceptibility near the critical point, and the critical exponent of the associated correlation length is obtained based on the finite size analysis.

We investigated the influence of the quantum-jump-based feedback on the behaviors of the three-level Rydberg system by making use of relative entropy coherence and the square root of quantum Jensen–Shannon divergence. It is shown that quantum relative entropy coherence and quantum Jensen–Shannon divergence are enhanced by particular quantum-jump-based feedbacks and increase with the enhancement of the detuning $ \delta $. We also explored the behavior of the entropic uncertainty relationship, and lower uncertainty bounds are obtained with quantum-jump-based feedbacks. The effect of different detunings $ \delta $ on the entropic uncertainty relationship is also discussed, and it is found that the uncertainty bound decreases when the detuning $ \delta $ increases.

We investigate the influence of weak measurement on the quantum-memory-assisted entropic uncertainty relation and quantum speed limit time in a quantum dissipative system by making use of the hierarchical equations of motion method. It is demonstrated that the weak measurement and measurement reversal can suppress the entropic uncertainty during the evolution of the system, and we find a periodical crossover of the quantum speed limit time for different weak measurement strengths, which disappears when increasing the coupling strength. Similar influence of the weak measurement on uncertainty relations is then explored at the finite temperature. We also consider the effect of the counter-rotating-wave term and show that the rotating-wave approximation is an applicable approximation when studying quantum speed limit time but not appropriate when investigating the quantum-memory-assisted entropic uncertainty relation.

Mg2Ni0.7M0.3(M=Al, Mn and Ti) alloys were prepared by solid phase sintering process. The phases and microstructure of the alloys were systematically characterized by XRD, SEM and STEM. It was found that Mg3MNi2intermetallic compounds formed in Mg2Ni0.7M0.3alloys and coexisted with Mg and Mg2Ni, and that radius of M atoms closer to that of Mg atom was more beneficial to the formation of Mg3MNi2. The hydrogen storage properties and corrosion resistance of Mg2Ni0.7M0.3alloys were investigated through Sievert and Tafel methods. Mg2Ni0.7M0.3alloys exhibited remarkably improved hydrogen absorption and desorption properties. Significantly reduced apparent dehydriding activation energy values of −46.12, −59.16 and −73.15 kJ/mol were achieved for Mg2Ni0.7Al0.3, Mg2Ni0.7Mn0.3and Mg2Ni0.7Ti0.3alloys, respectively. The corrosion potential of Mg2Ni0.7M0.3alloys shifted to the positive position compared with Mg2Ni alloy, e.g. there was a corrosion potential difference of 0.110 V between Mg2Ni0.7Al0.3alloy (−0.529 V) and Mg2Ni (−0.639 V), showing improved anti-corrosion properties by the addition of Al, Mn and Ti.

We investigate the quantum evolution speed of a qubit in two kinds of finite-temperature environments. For the first bosonic bath with an ohmic-like spectrum, the high temperature leads to not only the speed-up but also speed-down processes in the weak-coupling regime, which is different from the strong-coupling case, in which only the speed-up process is exhibited. Furthermore, we realize the controllable and stationary quantum evolution speed by applying the bang-bang pulse. For the second nonlinear bath, we study the quantum evolution speed by resorting to the hierarchical equations of a motion method beyond the Born–Markov approximation. It is shown that the quantum evolution speed can be decelerated by the rise of temperature in the strong-coupling regime, which is an anomalous phenomenon and contrary to the common recognition that quantum evolution speed always increases with the temperature.

We investigate the effect of quantum-jump-based feedback on the dynamics of quantum discord for two noninteracting two-level atoms coupled to a single mode of the cavity field with and without the rotating-wave approximation. It is found that the counterrotating terms can be helpful for generating steady states, and the value of steady-state quantum discord can be increased to approach 1 in the long-time limit by feedback controls. Furthermore, we also explore the influence of the time evolutions of mean excitation number in total systems and atomic subsystems on the quantum correlations and show that the enhancement of mean excitation number in atomic subsystems by feedback controls leads to the high value of steady-state quantum discord.

This paper introduce the thought of USB interface application, an automatic measurement system is as an example. The PC control system of automatic measurement by the Labview software programming, then control relay, and control the work state of the HP3. It shows that the design of USB interface application system is realized by using labview programming easy and high efficiency.

This paper aims to discuss about the method of HP3 interface program with hardware by Virtual instrument-labview. This paper studies the characteristic and advantages of labview, analyzes the HP3(Handyprobe difference USB oscilloscope) hardware interface way and discuss the connection on hardware labview. The actual interface connection method is given in the end.

We investigate how quantum measurements affect the dynamics of quantum correlations of the system which consists of two noninteracting superconducting qubits each locally coupling to its own data bus. It is shown that the geometric discord and entanglement between two superconducting qubits can be increased by applying a sequence of selective measurements. The optimal measurement time at which the quantum correlations achieve their maximal values is also analyzed. Moreover, we find that the selective measurements on the data buses can protect quantum information of two superconducting qubits and force information to flow back to the superconducting qubits from the data buses by a witness of the trace distance.

In this study IGC50 (50% inhibitory growth concentration) values of 26 nitrobenzenes were determined for population growth endpoint of Paramecium caudatum. Quantitative structure activity relationships (QSARs) were developed using log of the inverse of the IGC50 (logIGC50-1) in mole liter as the dependent variable and 6 molecular descriptors (logP, 1XⅤ, I, 1Ka, ∑σ- and ELUMO) as the independent variables. Through multiplicate regression analysis, one best QSAR equation was obtained. The equation was used to estimate IGC50 for 7 analogues.

The dynamics of classical correlation and quantum correlation of two qubits in an independent and common dissipative cavity are studied. We show that for an independent case, the quantum correlation keeps constant and the correlation relation decays before the critical time point Ωt¯. On the other hand t>Ωt¯, for the classical correlation does not change and the quantum correlation is lost. These situations demonstrate that the phenomenon of sudden transition between classical and quantum decoherence appears during the time evolution. For the common case, the quantum correlation dynamics is quite different. It is displayed that for some initial states, the quantum correlation can increase up to the critical point of time, after which it decreases, which means that the quantum correlation presents a sudden change of behavior in their decay rates. But for other initial states, the quantum correlation can keep increasing up to some-steady state value. Furthermore, we also investigate the nonzero quantum correlation between two qubits induced by the dissipation of the cavity.

We use an alternative approach to study the quantum phase transition in a coupled cavity lattice at finite temperature. As an illustrative example, we investigate the behaviors of the trace distance and quantum phase transition in a Jaynes-Cummings lattice at finite temperature. It is found that the trace distance can be used to describe the critical point of the quantum phase transition at finite low temperatures and the critical points are sensitive to the atom-field interaction strength and the detuning factor. For nonequilibrium states, we demonstrate that the time evolution of the trace distance's maximum value is also a good indicator of the critical points. Moreover, we show that the scaling behavior of the derivative of the trace distance at the critical points and the scaling rule are dependent on the external parameters of the Hamiltonian. [ABSTRACT FROM AUTHOR]

We investigate how to protect quantum correlations for two qubits each locally interacting with its own non-Markovian environment by making use of bang-bang pulses. It is shown that the quantum discord dynamics presents the phenomenon of sudden change for some certain initial states. We also find that the amount of quantum correlation between two qubits can be improved by applying a train of pulses and protected more effectively with shorter interval pulses or longer reservoir correlation time.

This paper deals with the method of simulating sea wave for decreasing its disturbance in the watercraft navigating. Firstly the ITTC two-parameter spectrum is selected as the power spectrum of sea wave to be simulated. Secondly the selected power spectrum is parted on a prescription composed of drugs of equal amount energy, and the harmonic frequency is determined by calculating the mass center of each section. Each order harmonic is synthesized on the basis of the Longuet-Higgins model in time domain. Finally, the simulation algorithm based on energy in part is presented and the simulated sea wave with time and space are determined. The simulation accuracy arrives at 1.6% compared with the ideal sea wave spectrum by the spectrum analysis of the simulated sea wave in Welch. That testifies the validity of this method and provides the watercraft movement parameters filtering with reliable exciting signals.

In order to improve the adaptability of the lane detection algorithm under complex conditions such as damaged lane lines, covered shadow, insufficient light, the rainy day etc. Lane detection algorithm based on Zoning Hough Transform is proposed in this paper. The road images are processed by the improved ±45° Sobel operators and the two-dimension Otsu algorithm. To eliminate the interference of ambient noise, highlight the dominant position of the lane, the Zoning Hough Transform is used, which can obtain the parameters and identify the lane accurately. The experiment results show the lane detection method can extract the lane marking parameters accurately even for which are badly broken, and covered by shadow or rainwater completely, and the algorithm has good robustness.

2,6-dinitrotoluene (2,6-DNT) is the preferential toxicants stipulated by OECD and EPA of USA. The present study was conducted to determine the effect of 2,6-DNT chemical on acute toxicity and subacute toxicity in common carp (Cyprinus carpio). The 24h, 48h, 72h and 96h LC50 values of common carp by 2,6-DNT were 1.137±0.023mg/L, 0.830±0.024mg/L, 0.661±0.019mg/L and 0.479±0.020mg/L, respectively. The subacute experiment shows that C. carpio are rarely affected by 0.0251mg/L 2,6-DNT, but significantly affected by 0.0398, 0.0631, 0.0794mg/L 2,6-DNT in contrast to the controlled sample (p liver > kidney.

As a result, CYP1A expression in fishes is frequently used as a biomarker of exposure to aromatic hydrocarbon contaminants and early biological effect. We determined EROD activity and cytochrome P4501A protein level in liver of feral fish, common carp, Cyprinus carpio inhabiting a nitrotoluene contaminated environment in this study. The results show that feral C. carpio caught from contaminated water(nitrotoluene)in Songhua River displayed induction of CYP1A at two levels of expression, namely, apoprotein level and catalytic activity in liver.

We investigate the quantum discord dynamics of two noninteracting two-level atoms, each trapped in a single-mode optical cavity which is filled with a nonlinear Kerr-like medium. It is found that quantum discord vanishes only asymptotically although entanglement disappears suddenly during the time evolution. Furthermore, we explore the influence of the nonlinear Kerr-like medium on the dynamics of quantum discord, quantum mutual information, and classical correlation of two atoms. It is shown that the amount of quantum discord, quantum mutual information, and classical correlation of two atoms can be improved by adjusting the value of the Kerr medium. Finally, we also study the effect of phase dissipation on this system by making use of the Monte Carlo wavefunction method.

Ultrafine CeO2 nanoparticles were prepared through a calcination method. The photocatalyst was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The performance of photocatalytic antibacterial was investigated by inactivation of E.coli. and S.aureus.

It has been shown that the topological term in theO(3) nonlinear d-model can be removed by a suitable canonical transformation using classical theory. In this paper, the quantum unitary transformation corresponding to the classical canonical transformation is presented. The meaning of the unitary transformation and the removability of the topological term are then discussed.

The basic invariants and general form of invariants are discussed for the harmonic oscillator with time-dependent mass. In the case of the damped harmonic oscillator, the explicit expression for the basic invariants is found. The basic invariants are then used to study squeezed states. Finally, the high-nsqueezed states are constructed.

In this paper, we find the exact solution for the generalized time-dependent harmonic oscillator by making use of the Lewis-Riesenfeld theory. Then, the adiabatic asymptotic limit of the exact solution is discussed and the Berry's phase for the oscillator obtained. We proceed to use the exact solution to construct the coherent state and calculate the corresponding classical Hannay's angle.

A path integral method is used to study the time evolution of a three-dimensional time-dependent system. The propagator for a charged particle in a time-dependent magnetic field and quadrupolar electric potential is obtained.

In this paper, the exact evolving state for a two-level quantum system is found by making use of the Lewis-Riesenfeld invariant theory. In principle, the correction to an arbitrary order in the adiabatic approximation parameter can be obtained from this exact evolving state. To the -th order in , it is shown that the exact evolving state reduces to the superadiabatic basis introduced by Berry recently. The Aharonov-Anandan phase and its adiabatic limit (Berry phase for the system) are also calculated.

The Lewis' invariant and exact solution for the driven generalized time-dependent harmonic oscillator is found by making use of the Lewis-Riesenfeld quantum theory. Then, the adiabatic asymptotic limit of the exact solution is discussed and the Berry's phase for this system is obtained. We then proceed to use the exact solution to construct the coherent state and calculate the corresponding exact classical phase angle. This phase angle can give the Hannay's angle in the adjabatic limit. The relation between the exact Lewis' phase and the corresponding classical phase angle is discussed.

We explore the quantum criticality in a one-dimensional quantum network, where adjacent nodes are connected by a fiber and each node consists of a cavity doped with N two-level atoms. We investigate the phase diagrams for cases of different atom numbers on resonance by making use of the mean-field approximation and find that both the fidelity and entanglement entropy for the ground state have dramatic changes near the critical points. Finally, the photon population imbalance of adjacent cavities is analytically explored via the two-node quantum network as the forerunner of phase transition.

This paper aims to discuss about impulse coupling calculation and fourier transform properties in the signal and system course teaching process. This paper analyzes the properties of fourier transform and the impulse coupling. Putting forward the reason and solve method of those questions.

We report on the electrochemical process and nucleation mechanism of the “direct-on-barrier” electroplating of copper on ultrathin cobalt adhesion layer from an alkaline CuSO4and ethylenediamine (En) bath without additives. Results show that the corrosion current density was much lower in the alkaline bath than that in the commercial acidic bath due to formation of the CuEn22+species in the aqueous CuSO4-En solution. The CuEn22+species can well stop the reaction between the copper ions and Co by reducing the potential of copper ions. The current-time transients were not typical of a diffusion-limited nucleation and growth. Pure instantaneous or progressive nucleation of copper on Co layer was not observed. The impact of current density on the orientation, resistance and morphology was studied. Copper film in 250 nm thick was successfully deposited on the 10 nm Co film in the patterned wafers. And Cu was electroplated onto ultrathin Co layer with ∼5 nm thickness and TEM result shows that there is no obvious Co thickness loss.

In this paper, the driven generalized time-dependent harmonic oscillator (DGTHO) is studied by making use of the new concept of quantum basic invariants. The connection between the quantum basic invariants and classical Noether's theorem is discussed. The classical basic invariants as well as the general form of classical invariants for the system are found. From these, we get the five Noether invariants and the set of corresponding infinitesimal generators {Gk}, hence, generalizing the work of G. Profilo and G. Soliani. Also, for the system, we calculate the current algebra which, as the central extension of the {Gk} algebra, should be regarded as the dynamical symmetry algebra for the system and is therefore more important than the {Gk} algebra. Finally, we demonstrate the existence of a kind of converse of Noether's theorem.