计算机控制光学表面成形中大规模驻留时间求解

采用基于稀疏矩阵的大规模非负最小二乘法,对大口径、微浮雕结构光学元件加工中的驻留时间进行了分析与求解,并对该算法开展了正则化研究。仿真结果表明:与传统非负最小二乘法相比,基于稀疏矩阵的大规模非负最小二乘法精度高、效率快。采用该算法仿真加工平均振幅为1.177 6倍波长的大口径、微浮雕结构光学元件,误差面形均方根收敛至0.067倍波长。     

Broadband 1.5-μm emission of high erbium-doped Bi2O3–B2O3–Ga2O3 glasses

High Erbium-doped glass showing the wider 1.5-μm emission band is reported in the Bi₂O₃–B₂O₃–Ga₂O₃ system and its thermal stability and optical properties such as absorption, emission spectra, absorption and stimulated emission cross-sections and fluorescence lifetime are investigated. Compared with other glass hosts, the gain bandwidth properties of high Er³⁺ content in BBG glass are better than those of tellurite, germanate, silicate and phosphate glasses. The broad and flat ⁴I_13/2→⁴I_15/2 emission and the larger stimulated emission cross-section of Er³⁺ ions around 1.5 μm enable it to be used as a host material for potential broadband optical amplifiers at C and L bands in the microchip configuration.     

Cosmological constraints from radial baryon acoustic oscillation measurements and observational Hubble data

We use the Radial Baryon Acoustic Oscillation (RBAO) measurements, distant type Ia supernovae (SNe Ia), the observational H(z)$H(z)$ data (OHD) and the Cosmic Microwave Background (CMB) shift parameter data to constrain cosmological parameters of ΛCDM$\mathrm{\Lambda }\text{CDM}$ and XCDM cosmologies and further examine the role of OHD and SNe Ia data in cosmological constraints. We marginalize the likelihood function over h   by integrating the probability density P∝e−χ²/2$P\propto e^{-{\chi }^2/2}$ to obtain the best fitting results and the confidence regions in the Ωm–ΩΛ${\Omega }_m\text{–}{\Omega }_{\Lambda }$ plane. With the combination analysis for both of the ΛCDM$\mathrm{\Lambda }\text{CDM}$ and XCDM models, we find that the confidence regions of 68.3%, 95.4% and 99.7% levels using OHD+RBAO+CMB$\text{OHD}+\text{RBAO}+\text{CMB}$ data are in good agreement with that of SNe Ia+RBAO+CMB$\text{Ia}+\text{RBAO}+\text{CMB}$ data which is consistent with the result of Lin et al.'s (2009) [24] work. With more data of OHD, we can probably constrain the cosmological parameters using OHD data instead of SNe Ia data in the future.     

H^＋与He原子碰撞中电子俘获截面的BIB方法计算

用考虑边界修正的一级玻恩畸变波方法（ＢＩＢ）计算了质子与Ｈｅ原子碰撞中的电子俘获面。结果表明在所关心的能区（１００ｋｅＶ～２４００ｋｅＶ）与实验结果较好地一致     

The investigation of electrochemical properties and ionic motion of functionalized copolymer electrolytes based on polysiloxane

The effect of EO side chain functionalization on the transport and electrochemical properties of polysiloxane electrolytes has been examined in this report. First, a study of the electrochemical stability of the electrolytes by linear sweep voltammetry shows that the polymer electrolytes have a negligible effect on the electrolyte stability windows. In addition, the parameters of cation mobility in polysiloxane electrolytes, such as ionic transference numbers and diffusion coefficients, were increased by increasing the lengths of the EO side chain. However, cation mobility in polymer structures is quite different compared to liquid-based systems and is probably suppressed, resulting in their polymer structure. Therefore, Positron Annihilation Lifetime Spectroscopy (PALS) was used to study the relationship between orthopositronium (o-Ps) lifetime, free volume radius, free volume of micro voids and EO side chain affection at different temperatures. Finally, a battery application with LiCoO₂ and LiFePO₄/polymer electrolyte/lithium metal electrode was monitored for its potential use in the future.     

Entanglement dynamics in Coriolis coupled rovibrational states of formaldehyde

The entanglement dynamics of two vibrational modes of a polyatomic molecule coupled by Coriolis interaction to overall molecular rotation is studied in terms of two negativities, N(t) and N_s(t), respectively, defined by the minimum of the eigenvalues and by the sum of the negative eigenvalues of the partial transpose of a density matrix. Various initial states are the products of Dicke states and the products of coherent states of vibrations and rotations. Formaldehyde is taken as an example, and the von Neumann entropy s(t) is simulated for the comparison with both negativities. It is shown that negativity N_s(t) is positively correlated with entropy s(t), and the correlated behavior between negativity N(t) and entropy s(t) strongly depends on initial states. However, these three indicators of entanglement display a dominantly positive correlation for the coherent states with small or large parameters. In addition, for the latter state two quantities N(t) and s(t) are nearly unchanged for a long time. This time can be further increased by the increasing of vibrational quantum number so that molecular information processing and quantum computing is allowed. These results are useful in quantum information theory.     

掺Yb钒酸盐晶体激光振荡中的光学双稳态现象研究

研究了三种掺Yb钒酸盐晶体Yb:LuVO4,Yb:YVO4和Yb:GdVO4的激光振荡中所呈现的光学双稳态效应.以晶体所吸收的抽运功率表征的双稳区宽度ΔPabs可超过1W,在双稳区高功率一侧的边界,即激光振荡的上阈值点,出现激光输出功率的不连续变化或跃变,同时发生亚毫秒时间尺度上的大幅度强度涨落.谐振腔的输出耦合透过率、晶体长度、晶体中的热效应等对双稳态效应均具有重要影响.     

2-μm emission performance of Tm~(3+)-Ho~(3+) co-doped tellurite glasses

The emission properties of 2-μm region fluorescence of Tm~(3+)-Ho~(3+) co-doped tellurite glasses are investigated. Introducing F~- ions to the composition of tellurite glasses plays a positive effect on the 2-μm emission.A maximum intensity of 2-μm emission is achieved when 1.5-mol%Tm_2O_3 and l-mol% Ho_2_O3 concentration are doped in the glasses.The emission cross section and gain coefficient of the ~5I_8→~5I_7 transition of Ho~(3+) are calculated.The emission cross section has a maximum of 1.29×10~(-2...     

一种基于多目标约束的互连线宽和线间距优化模型

优化线宽和线间距已经成为改善系统芯片性能的关键技术.本文基于互连线线宽和线间距对互连延时、功耗、面积和带宽的影响,提出了基于多目标优化方法实现优化线宽和线间距的思路,并利用曲线拟合方法得到了多目标约束的解析模型.Hspice验证结果显示,该解析模型精度较高,平均误差不超过5%,算法简单,能有效弥补应用品质因数方法的缺陷,可以应用于纳米级互补金属氧化物半导体系统芯片的计算机辅助设计.     

二氧化硅分子配分函数的研究

在低温20K到高温6000K温度范围内,计算了¹⁶O²⁸Si¹⁶O分子稳定结构的的总配分函数.其中,转动配分函数考虑了离心扭曲修正,振动配分函数采用谐振子近似.把20—6000K的温度范围划分为五区间段,计算的总配分函数在这五个温度区间分别被拟合到一个温度T的四阶多项式,从而在每个区间均得到五个拟合系数.由这些拟合系数就可以快速、准确地获得分子在所研究温度范围内任意温度的总的配分函数. 关键词： 总配分函数 二氧化硅分子 转动配分函数 振动配分函数