Tunneling Dynamics Between Any Two Multi-atomic-molecular Bose-Einstein Condensates

Tunneling dynamics of multi-atomic molecules between any two multi-atomic molecular Bose-Einstein condensates with Feshbach resonance is investigated. It is indicated that the tunneling in the two Bose-Einstein condensates depends not only on the inter-molecular nonlinear interactions and the initial number of molecule in these condensates, but also on the tunneling coupling between them. It is discovered that besides oscillating tunneling current between the multi-atomic molecular condensates, the nonlinear multi-atomic molecular tunneling dynamics sustains a self-locked population imbalance: a macroscopic quantum self-trapping effect. The influence of de-coherence caused by non-condensate molecule on the tunneling dynamics is studied. It is shown that de-coherence suppresses the multi-atomic molecular tunneling.     

The Dynamics of Quantum Correlations Between Two Atoms in Two Coupled Cavities

The dynamics of the quantum correlation between two atoms in two single-mode cavities is studied. For the initial Bell state |Ψ ⁺〉, the quantum consonance is equal to the entanglement, and larger than quantum discord. For the initial Bell state |Φ ⁺〉, the quantum consonance is larger than entanglement, but not larger than quantum discord all the time. As the increase of the cavity-cavity coupling strength, the evolution period of quantum correlation becomes smaller. Consonance is not smooth at some points while cavities are coupled with each other.     

Self-Trapping of Two Weakly Coupled Bose-Einstein Condensates with Oscillating Atomic Scattering Length

We investigate the self-tapping phenomena for two weakly coupled Bose-Einstein condensates with a rapid periodic modulation of the atomic scattering length. By using an averaging method, the equations of motion of the slow dynamics are derived to analyze the self-trapping behavior. It is shown numerically that under certain conditions, an alternative self-trapping in either well appears.     

Anti-synchronization Between Coupled Networks with Two Active Forms

This paper studies anti-synchronization and its control between two coupled networks with nonlinear signal's connection and the inter-network actions. If anti-synchronization does not exist between two such networks, adaptive controllers are designed to anti-synchronize them. Different node dynamics and nonidentical topological structures are considered and useful criteria foranti-synchronization between two networks are given. Numerical examples are presented to show the efficiency of our derived results.     

Steady-State Discord Between Two Qubits Coupled Collectively to a Thermal Reservoir

We study the dynamics of quantum discord between two qubits coupled collectively to a thermal reservoir. For comparison, we also consider the dynamics of quantum entanglement. It is shown that we can obtain a stable quantum discord induced by the thermal environment when the discord of the initial state is zero. The thermal environment can also induce a stable amplification of the initially prepared quantum discord for certain X-type states. It is very valuable that the quantum discord is more resistant against the thermal environment than quantum entanglement. And, we have demonstrated that the sudden death of discord in a Markovian regime is impossible even at high temperature. It provides us a feasible way to create and protect quantum correlation in the case of a high-temperature thermal environment for various physical system such as trapped ions, quantum dots or Josephson junctions.     

Lag Synchronization Between Two Coupled Networks via Open-Plus-Closed-Loop and Adaptive Controls

In this paper,we study lag synchronization between two coupled networks and apply two types of control schemes,including the open-plus-closed-loop(OPCL) and adaptive controls.We then design the corresponding control algorithms according to the OPCL and adaptive feedback schemes.With the designed controllers,we obtain two theorems on the lag synchronization based on Lyapunov stability theory and Barbalat's lemma.Finally we provide numerical examples to show the effectiveness of the obtained controllers and see that the adaptive control is stronger than the OPCL control when realizing the lag synchronization between two coupled networks with different coupling structures.     

Asymptotic Behavior of the Solutions of a System of Two Weakly Coupled Relaxation Oscillators with Delayed Feedback

Radiophysics and Quantum Electronics - We consider a dynamic system that consists of two coupled self-excited oscillators with delayed feedback. Such models occur in applied problems of radio...     

Anti-synchronization Between Two Coupled Networks with Unknown Parameters Using Adaptive and Pinning Controls

In this paper, we study anti-synchronization between two coupled networks where the node dynamics has an unknown system parameter. By designing adaptive and pinning control schemes, we realize the anti-synchronization.By Lyapunov stability theory, we obtain two theorems on the appearance of anti-synchronization. In addition, we derive a criterion for the pinning number of nodes. Finally we provide two numerical examples to show the effectiveness of our proposed control schemes. When the anti-synchronization is achieved, we successfully identify the unknown system parameter.     

双压电材料三维界面端部力电耦合场奇异性

基于切口根部物理场的幂级数渐近展开假设,从三维应力平衡方程和麦克斯韦方程组出发,导出关于双压电材料楔形界面切口端部奇性指数的特征微分方程组,并将切口的力电学边界条件表达为奇性指数和特征角函数的组合,从而将双压电材料楔形界面切口端部奇性指数的计算转化为相应边界条件下常微分方程组特征值的求解,运用插值矩阵法求解界面端部若干阶应力奇性指数和相应特征函数.计算结果与已有结果对比表明本文方法的有效性和具有较高的计算精度.     

Coupling Effect of Atomic Tunneling States with Local Vibration Modes in Amorphous Materials1

Considering the coupling of the atomic tunneling states with the vibration modes of its nearby atoms, two different kinds of double-well potentials are obtained. At the meantime, the vibration of nearby atoms are softened, and under certain conditions a new double-wel1,potential of higher rank can be induced which makes a hierarchical double-well potential structure possible.     

弯曲纳米光纤的耦合问题研究

从纳米光纤倏逝波角度出发,采用时域有限差分法数值模拟了两根弯曲纳米光纤耦合区域附近的空间光强分布,给出耦合效率随两弯曲光纤间距、光纤半径、弯曲半径等参量变化的曲线.结果表明:两根纳米光纤之间可以有效传递光能,其耦合效率随两弯曲光纤间距、光纤半径、弯曲半径等参量均有关.     

Exact Form Factors for the Josephson Tunneling Current and Relative Particle Number Fluctuations in a Model of Two Coupled Bose–Einstein Condensates

Form factors are derived for a model describing the coherent Josephson tunneling between two coupled Bose–Einstein condensates. This is achieved by studying the exact solution of the model with in the framework of the algebraic Bethe ansatz. In this approach the form factors are expressed through determinant representations which are functions of the roots of the Bethe ansatz equations.     

Optimal Dense Coding and Swap Operation Between Two Coupled Electronic Spins: Effects of Nuclear Field and Spin-Orbit Interaction

The effects of nuclear field and spin-orbit interaction on dense coding and swap operation are studied in detail for both the antiferromagnetic (AFM) and ferromagnetic (FM) coupling cases. The conditions for a valid dense coding and under which swap operation is feasible are given.     

锥形光纤间耦合特性的分析与检测

将通信光纤的末端拉制成锥形，利用光信号在光纤锥形区特有的传输和耦合特性，实现了光纤的耦合、连接和分束。用耦合模理论分析了锥形光纤间的传输和耦合性质，给出了光信号两锥形光纤间的耦合与两锥形光纤的距离和锥形区重叠长度等实验结果。     

The Relation Between the Two Methods for Describing Markovian Noises

A general method used to calculate the time-dependent probability distribution from the switching time distribution ψ(t, a) and the transition probability ρ(a, b) for Markovian noises is presented, and the way how to describe the noises treated as diffusion processes such as O-U noise by the jump model (namely, ψ(t, a) and ρ(a, b)) is given, which makes it possible to apply the stochastic trajectory technique and the definition method to the above noises.     

单模辐射场与耦合双原子Raman相互作用过程中原子的偶极压缩特性

研究了单模辐射场与耦合双原子Raman相互作用过程中原子的偶极压缩特性，讨论了系统耦合常数和初始状态对原子偶极压缩的影响。     

The Quantum Fluctuations of Two Coupled Josephson Junctions with the Discreteness of Electric Charge

The quantization of two Josephson junctions coupled via inductor with the discreteness of electric charges is proposed. The finite-difference Schrodinger equation of the circuit system has been obtained in charge representation, and the Schrodinger equation is turned to be Mathieu equation in flux representation. The wavefunction and energy spectrum can be solved by adopting the canonical transformation and unitary transformation method. The results indicate that the quantum fluctuations of the flux in the ground states of each mesh exist and are interrelated.     

The Relation Between Two Types of Characteristic Equations for Quantum Matrices

A definition (modification) of the power of quantum matrices using the -matrix has recently been proven useful to obtain generalizations of many well known theorems from linear algebra to the quantum case, among which are the Cayley–Hamilton theorem and the Newton identities. A separate effort has provided another generalization of the Cayley–Hamilton theorem for GL _q (n), which uses usual matrix powers but diagonal matrices as coefficients.We show that the latter generalization can be derived in the aforementioned more general framework and it is the expression of the modified quantum power in terms of the usual ones that accounts for the appearance of diagonal matrices.     

结构和磁场对三势垒结构中共振隧穿时间的影响

为了理解在三势垒结构中准束缚能级Ez和隧穿寿命对磁场的依赖性,采用传输矩阵的方法研究了在三势垒结构中的共振隧穿过程。分别研究了在三势垒结构中的透射几率特征和隧穿寿命。结果表明:随着中间势垒厚度L的增加,第一准束缚能级E1z增加,而第二准束缚能级E2z却减小。随着磁场强度B和朗道量子数n的增加,与第一和第二准束缚能级(E1z,E2z)对应的寿命τ缩短。对于B=15和n=15的情况,L对τ的影响很小。     

耦合双原子与单模压缩相干态光场的相互作用

利用全量子理论,在相互作用绘景中研究了两个耦合二能级原子与单模压缩相干态光场相互作用系统粒子布居几率的时间演化规律;分别讨论了光场的相干振幅分量模平方｜α｜２、光场的压缩因子γ、原子间的耦合系数g和原子-场的耦合系数λ对系统粒子布居几率的影响.