CMOS兼容的中红外多通道光子晶体传感器（英文）

提出了一种基于光子晶体的二维多通道光学化学传感器。该器件由中心波长为3.3μm的四个腔组成,各通道工作波长间隔为10 nm。该传感器采用800 nm厚的绝缘体上硅材料,可利用标准CMOS技术加工。通过三维时差有限差分法对微腔结构的光学特性进行模拟。每个通道的传输效率为39%,通道之间的传输效率不一致性小于0.25dB。该传感器的功能为检测四氯化碳和苯溶液浓度,其灵敏度为209.2 nm/RIU。     

高效的光子晶体6-信道下载滤波器的设计

基于二维光子晶体波导与点缺陷微腔共振耦合原理,设计了一种利用共振微腔作为反射的6-信道下载滤波器.采用二维时域有限差分法对该结构器件的传输性能进行了模拟,结果表明该结构的滤波器能将主波导中的波分复用信号下载至与点缺陷频率共振的各分路波导中输出,信道波长间隔为20nm,传输谱中心波长误差小于±2nm,半宽度为3.4nm,具有良好的波长选择性.证实了加入共振反射微腔确实有效地提高了各个分路的下载效率,其效率在67%～98%之间.     

雪粒径对积雪双向反射率的影响

雪粒径大小影响着积雪反照率的高低,从而影响着局地或全球能量收支平衡和气候变化,其影响程度取决于积雪本身的微物理特征和光学特性。在研究550nm、1030nm和1640nm波长处积雪光学特性的基础上,采用辐射传输方程模拟并分析了雪粒径对积雪双向反射率的影响。模拟结果表明近红外通道1030nm是反演雪粒径的敏感波长,积雪双向反射率在该波段随粒径和观测角度变化明显,多角度遥感信息可以更有效地体现积雪的微物理特征和光学特性,为利用多角度遥感数据反演雪粒径提供理论基础。     

四镜8字环形腔激光器的设计与实验研究

采用ABCD传输矩阵计算方法结合Matlab软件进行模拟计算,设计热稳定性良好的四镜8字环形激光谐振腔。该环形谐振腔在高功率泵浦条件下,腔模参数随热透镜焦距变化具有良好的稳定性。在腔内插入由法拉第旋光器和半波片组成的光学单向器,实现了单向运转。在泵浦功率为40 W时,获得最高功率为14 W的连续波单向1064 nm波长激光输出,光光转换效率为35%。     

GaAs基MOEMS波长可调谐滤波器的设计和理论模拟

采用传输矩阵理论和结合悬臂梁的电学一机械模型对GaAs基1.55 μm微光电机械系统(MOEMS)波长可调谐滤波器的光学和电学特性进行了深入的对比分析和研究.结果表明,采用800 nm厚的空气腔可以实现滤波器波长的调谐范围为100 nm,所需最大反向偏压为4 V,波长的调谐速率可以达到1.83 MHZ.     

在神光Ⅱ装置第九路系统开展351nm波长激光高通量传输的实验研究

提出一种可实现351 nm波长激光高通量传输的终端光学组件(FOA)的物理设计方案,研究了设计优化方法,并利用神光Ⅱ装置第九路系统开展了实验研究。实验共进行了33发激光发射:激光光束净口径310 mm,时间脉冲宽度3 ns,1053 nm波长激光能量1000~4500 J。实验获得最高三次谐波转换效率69.6%和351 nm波长激光传输通量3.76 J/cm2,同时监测到高通量激光传输引起的动态环境污染物颗粒变化数和光学元件激光诱导损伤等现象。实验结果表明,通量密度约为3 J/cm2@351 nm的光学元件损伤主要是由激光传输散射鬼光束辐照材料所激发的污染物所致。     

高光谱成像传感器

Photon etc公司推出一批基于布拉格可调光栅滤光片的高光谱成像传感器。这种传感器能够在紫外-可见光-近红外的任何波长处获取图像,其光学带通为0.25nm～100nm和350nm～2.5μm,非偏振光的效率     

双波长可调外腔半导体激光器

提出了一种基于体布拉格光栅（VBG）和横向啁啾体布拉格光栅（TCVBG）组合的双光栅外腔半导体激光器,该外腔半导体激光器采用反射率15%的体光栅和反射率17%的啁啾体布拉格光栅作为反馈元件和模式选择元件,实现特定波长的选择和调谐,实验研究了外腔激光器的功率-电流特性、光谱特性和波长调谐特性。实验结果表明:双光栅外腔半导体激光器最大输出功率为1.96 W,斜率效率为0.94 W/A,外腔效率达到78%。输出光谱为双波长,一个波长为808.6 nm,另一个波长连续可调,通过改变横向啁啾体光栅的位置,该波长可从800 nm调谐至815 nm,可调范围达15 nm,在整个可调范围内两个波长的谱线宽度（FWHM）均小于0.3 nm。     

利用外腔谐振倍频获得双色量子关联光场

报道了利用周期极化铌酸锂晶体外腔谐振增强倍频技术获得波长分别为1560 nm和780 nm双色量子关联光场。由于该量子关联系统的激光波长分别位于量子态传输波段与原子存储波段,可应用于研究实用化量子信息处理系统。在利用谐振倍频获得10 m W倍频光输出、倍频效率达45%的基础上,实测1560 nm基频光与780 nm倍频光的量子关联为1.2 d B。     

基于马赫曾德尔干涉结构的硅基波分复用器

文章提出了一种基于马赫曾德尔干涉结构的硅基 波分复用器。该器件可通过集成的电 光移相器实现对器件中各通道传输谱的调节,来补偿外界温度变换和工艺误差造成的波长漂 移。测试结果表明,热光移相器的效率为3mW/π,可以实现4个通道的波分复用,通道间隔 为3.3 nm,隔离度大于30 dB。     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

Propagation of hermite-cosh-gaussian beams passing through ABCD optical system with an annular aperture

By using the expansion of the aperture function into a finte sum of complex Gaussian functions, the corresponding analytical expressions of Hermite-cosh-Gaussian beams passing through annular apertured paraxially and symmetrically optical systems written in terms of ABCD matrix were derived, and they could reduce to the cases with squared aperture. In a similar way, the corresponding analytical expressions of cosh-Gaussian beams through annular apertured ABCD matrix were also given. The method could save more calculation time than that by using the diffraction integral formula directly.     

Noise character analysis and the restraint of self-pulsation laser diodes

We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.     

Influence of polarization extinction ratio on distributed polarization coupling detection

Distributed polarization coupling in polarization-maintaining fibers can be detected by using a white light Michelson interferometer. This technique usually requires that only one polarization mode is excited. However, in practical measurement, the injection polarization direction could not be exactly aligned to one of the principal axes of the PMF, so the influence of the polarization extinction ratio should be considered. Based on the polarization coupling theory, the influence of the incident polarization extinction on the measurement result is evaluated and analyzed, and a method for distributed polarization coupling detection is developed when both two orthogonal eigenmodes are excited.     

High-quality single-crystal CdSe nanoribbons and their optical properties

Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method, in which two-step-thermal-evaporation is used to control CdSe sources＇ evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width, 50 nm in thickness, and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photolumines-cence indicates that the lasing emission at 710 nm has been observed under optical pumping （266 nm） at power densities of 25-153 kW/cm^2. The full width half maximum （FWHM） of the lasing mode is 0.67 nm     

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正Communications—VLSI Researches and industries of telecommunications have been growing rapidly in the last 20 years and will keep their high growing pace in the next decade.The involved researches and developments cover mobile communications,highway and last-mile broadband communication,domain specific communications,and emerging D2D M2M communications.Radio communication steps into its