Evolution of spin-dependent atomic wave packets in a harmonic potential

We have investigated theoretically the evolution of spin-dependent atomic wave packets in a harmonic magnetic trapping potential. For a Bose-condensed gas, which undergoes a Mott insulator transition and a spin-dependent transport, the atomic wavefunction can be described by an entangled single-atom state. Due to the confinement of the harmonic potential, the density distributions exhibit periodic decay and revival, which is different from the case of free expansion after switching off the combined harmonic and optical lattice potential.     

含Laplace-Gauss型混合噪声图像二阶正则化重建方法

假设观测数据含Laplace-Gauss型混合噪声条件下,提出求解数据重建反问题的一种新型一阶二阶混合正则化模型,阐述该模型在断层重建和流体动力学实验定量诊断中的应用.建模过程采用贝叶斯推断理论和期望极大方法,将空间自适应函数引入经典的增广拉格朗日方法得到模型数值算法.所提出的模型及其算法进行图像复原和客体重建实验.结果表明模型算法的可靠性.     

费尔德常数到底有多大?

当线偏振光穿越媒质时,由于沿传播方向的磁场影响,振动面将要转动。这种现象称为法拉第效应或磁光效应。振动面旋转的角度θ由以下经验公式给出: θ=VBd,式中B为磁感应强度,d为穿越媒质的长度,比例系数V称为费尔德(Verdet)常数,其数值由实验测定。 我们比较了国内外出版的手册和书籍所列出的费尔德常数值,发现出人颇大,有的甚至差几个量级。有些书中的数值相同,但单位不同。换算成同一单位,则大小就相差甚远了。可见把单位搞错,也可能是以讹传讹的原因之一。经笔者核对,文献[1][2][3]所给的V值彼此相符,可认为它们是正确的。由于各方面条…     

羧基化碳纳米管存在下茜素红-蛋白质的光散射光谱研究

本文报道了羧基化碳纳米管存在下茜素红-蛋白质的光散射光谱。与无羧基化碳纳米管时相比,其散射光强度明显增加。优化了影响体系光散射检测的实验参数。在实验选定最佳条件下,考察了散射光强度与蛋白质浓度的关系,发现在362 nm波长处散射光强度与牛血清蛋白(BSA)和人血清蛋白(HSA)浓度均在0.10～9.0 mg/L范围内呈线性关系,其检出限为0.053 mg/L。将该法用于人血清总蛋白含量的测定,结果令人满意。     

含Laplace-Gauss型混合噪声图像二阶正则化重建方法（英文）

假设观测数据含Laplace-Gauss型混合噪声条件下,提出求解数据重建反问题的一种新型一阶二阶混合正则化模型,阐述该模型在断层重建和流体动力学实验定量诊断中的应用.建模过程采用贝叶斯推断理论和期望极大方法,将空间自适应函数引入经典的增广拉格朗日方法得到模型数值算法.所提出的模型及其算法进行图像复原和客体重建实验.结果表明模型算法的可靠性.     

冷85Rb原子D2线电磁诱导透明的实验研究

对85Rb原子D2线三能级系统的电磁诱导透明进行了详细的实验研究.得到了不同耦合强度下探测光的吸收线型,并对气室中热原子与磁光阱中冷原子的电磁诱导透明光谱进行了比较.     

Squeezing via coupling of Bose--Einstein condensates in a double-well potential with a cavity light field

Squeezing via the interaction between the cavity light field and the Bose Einstein Condensate （BEC） in a doublewell potential is considered within the context of the two-mode approximation. For the cavity light field initially in a coherent state, it is shown that by choosing appropriate parameters, quadrature squeezing of the cavity light field can be achieved and it exhibits periodic oscillation. We also study the case in which BEC is tuned to resonance by periodically modulating the trapping potentiaL and the quadrature squeezing of the cavity field exhibits periodic collapse and revival effect. Both analytic and numerical calculations are performed, and they are found to be in good agreement with each other. The result shows that the quantum statistical properties of the cavity light field can be manipulated by its coupling with the condensates in the double-well potential. On the other hand, dynamical properties of the condensates in the double-well potential will be reflected by the quadrature squeezing of the light field.     

现场电聚合法制备锂二次聚合物电池的研究

基于1,3-二氧戊环(DOL)的可聚合特征, 提出了一种新的聚合物锂二次电池的现场制备方法, 并对其进行研究. 电化学实验表明: 在特定的电流密度下, 仅通过常规的恒电流充放电处理就能实现聚合物锂二次电池的现场组装, 得到的聚合物锂二次电池在电化学性能上与普通液态锂二次电池相当. 紫外-可见光谱表明, 通过一定的电化学处理, DOL能够发生电聚合, 扫描电镜以及交流阻抗测试也证明DOL的聚合不仅实现了液态电解液向聚合态的转变, 而且有助于在电极表面生成较为稳定的聚合物层.