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1.
快速循环晶化Al/BiGaDyIG双层膜的研究结果表明,由于晶粒细化及膜层间干涉增强效应,在0.1~1.3μm膜厚范围.其平均有效法拉第角比单层膜增加了0.25°,且随循环次数增加而增大。同时.部分AI3+离子在退火期间扩散进石榴石的八面体和四面体位,导致居里温度下降(140~161μ)。这些结果对提高石榴石磁光盘信噪比以及增大记录密度是极有意义的。  相似文献   

2.
万云  张湘云 《激光与红外》1998,28(4):215-216,219
研制了具有约瑟夫逊效应的高TcGdBa2Cu3O7-δ薄膜双晶晶界结,按照光助隧道效应的原理我们用双晶结进行光探测,光源是波长为0.6328μm的He-Ne激光器,系统观测了高Tc GdBa2Cu3O7-δ双晶结的光响应特性,最好的结果为:噪声等效功率NEP=4.3×10^-14WHz^-1/2,归一化探测率D^8=1.2×10^10cmHz^1/2W^-1,响应率Rv=3.5×10^7V/W,  相似文献   

3.
用且熔剂法生长出(YbTbBi)3Fe5O12块状单晶,测量了该单晶在1.0~1.7μm范围的Faraday旋转谱及透射谱,当温度为10~80℃,λ=1.55μm时,测得该单晶的Farady旋转温度系数为2.0×10^-2(°).mm^-1.K^-1,所得结果表明:(YbTbBi)3Fe5O12单晶既有较大的Faraday旋转角,又有很小的温度系数。  相似文献   

4.
(YbTbBi)_3Fe_5O_(12)块状单晶生长及其磁光性能   总被引:2,自引:2,他引:0  
用助熔剂法生长出(YbTbBi)3Fe5O12块状单晶,测量了该单晶在1.0~1.7μm范围的Faraday旋转谱及透射谱.当温度为10~80℃,λ=1.55μm时,测得该单晶的Faraday旋转温度系数为2.0×10-2.(°)·mm-1·K-1.所得结果表明:(YbTbBi)3Fe5O12单晶既有较大的Faraday旋转角,又有很小的温度系数  相似文献   

5.
硅基GaAs/GaAlAs平面光波导的研究   总被引:1,自引:0,他引:1  
分析了金属有机化合物化学气相淀积(MOCVD)GaAs/GaAsAl/GaAs/Si材料结构的性能,用MOCVD法地硅衬底上生长了GaAs/GaAsAl/GaAs材料,并用这种材料制备了平面光波导样品,测定了1.3μm,单模激光的传输损耗小于0.65dB/cm。  相似文献   

6.
对1.3μm和1.55μm波长的Si1-xGex波长信号分离器(WSD)和Si1-xGex/Si应变超晶格(SLS)红外探测器的集成结构进行了系统的分析和优化设计.优化结果为:(1)对Si1-xGexWSD,Ge含量x=0.05.波导的脊高和腐蚀深度分别为3μm和2.6μm.对应于λ1=1.3μm和λ2=1.55μm波长的波导脊宽分别为11μm和8.5μm.(2)对Si1-xGex/SiSLS探测器,Ge含量x=0.5.探测器的厚度为550nm,由23个周期的6nmSi0.5Ge0.5+17nmSi组成.  相似文献   

7.
偏振有关光隔离器性能的理论分析   总被引:1,自引:0,他引:1  
本文系统地分析了偏振有关光隔离器的性能,讨论了光隔离器中各元件的加工精度、表面反射率以及光纤耦合等因素对光隔离器特性的影响。理论分析表明,当各元件表面的光强反射率<0.25%,45°法拉第旋转器的法拉第旋转误差<4.3°,偏振器P1和P2透光轴之间的夹角误差<0.57°时,可以得到隔离度>40dB、正向损耗<0.9dB的光隔离器。在实验中,我们已成功地研制了1.55μm和1.3μm带尾纤的光隔离器,隔离度>40dB、正向损耗<l.5dB。  相似文献   

8.
在运用SiGe脊形波导单模条件和有效折射率法分析SiGe/Si定向耦合器结构参数的基础上,采用分子束外延和各向异性腐蚀技术制备出Si1-xGex/Si(x=0.05)单模定向耦合器.在波长为1.3μm时,平均串音小于-18.1dB,输出功率耦合效率达到98.1%  相似文献   

9.
用GexSi1-x/Si亚稳材料在高温下制作了光波导,它的传输损耗为0.8dB/cm,比低温工艺的0.5dB/cm稍大。并发现GexSi1-x/Si材料的大量失配位错的一些有趣的现象。  相似文献   

10.
用GexSi1-x/Si亚稳材料在高温下制作了光波导,它的传输损耗为0.8dB/cm,比低温工艺的0.5dB/cm稍大。并发现GexSi1-x/Si材料的大量失配位错和一些有趣的现象。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

14.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

15.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

16.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.  相似文献   

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