二维电磁感应光子带隙的动态生成与调控

研究了由两个垂直传播的强驻波激光场共同耦合的一个四能级Tripod型冷⁸⁷Rb原子介质的稳态光学响应特性. 结果发现, 当两驻波场满足双光失谐条件时, 可在这两驻波场的传播方向上同时获得反射率高达95%以上的电磁感应光子带隙结构; 通过适当调节强激光场, 还可实现一个方向为光子带隙而另一个方向为透明窗口或者两个方向均为透明窗口的结构. 并且光子带隙和透明窗口的频宽和位置是可调谐的. 这种全光控制的二维的信号光禁闭和导通机制可用于实现全光开关和全光路由, 有利于复杂的全光通讯网络的开发. 关键词： 相干诱导光子带隙 电磁感应透明 周期调制原子相干     

基于Kriging代理模型的船舶水动力性能多目标快速协同优化

引入Kriging代理模型,对船舶兴波阻力、垂荡和纵摇运动幅值进行了多目标快速优化.优化过程中,以Rankine源非线性势流理论和三维频域面元法为基础,利用非支配排序遗传算法(NSGA-Ⅱ)并结合船体曲面修改函数对船体型线进行多目标优化设计,将高精度Kriging代理模型引入到优化进程中以解决迭代造成的耗时难题.数值分析结果表明:该优化方法能够使船型最优,在设计吃水、服务航速下有效减少航行阻力并提高耐波性能,且Kriging代理模型方法可以大幅提高船型优化效率.最后,基于雷诺平均(RANS)方程的计算流体动力学(CFD)方法对模型尺度λ为31.599的最优船型的阻力结果进行了对比验证,以证明优化结果的可靠性.     

Birman-Wenzl-Murakami Algebra and Topological Basis

In this paper,we use entangled states to construct 9 × 9-matrix representations of Temperley-Lieb algebra(TLA),then a family of 9× 9-matrix representations of Birman-Wenzl-Murakami algebra(BWMA) have been presented.Based on which,three topological basis states have been found.And we apply topological basis states to recast ninedimensional BWMA into its three-dimensional counterpart.Finally,we find the topological basis states are spin singlet states in special case.     

在初中数学教学中培养学生的整体观察能力

例1 解方程 分析 通过整体观察不难发现互为倒数,故原方程可转化为     

A 9× 9 Matrix Representation of Birman-Wenzl-Murakami Algebra and Berry Phase in Yang-Baxter System

We present a 9×9 S-matrix and E-matrix. A representation of specialized Birman-Wenzl-Murakami algebra is obtained. Starting from the given braid group representation S-matrix, we obtain the trigonometric solution of Yang-Baxter equation. A unitary matrix \breve{R}(x,φ₁,φ₂) is generated via theYang-Baxterization approach. Then we construct a Yang-BaxterHamiltonian through the unitary matrix \breve{R}(x,φ₁,φ₂). Berry phase of this Yang-Baxter system is investigated in detail.