铷原子法拉第共振滤光特性研究

我们在不同磁场强度、原子气体密度下，实验观测了７８０ｎｍ铷原子气体的法拉第共振滤光效应，并进行了理论分析。结果表明：透射峰中心频率的调谐能力为￣１００ＧＨｚ／Ｔ，透过率大于４０％，通频带宽为０．００１ｎｍ￣０．０１ｎｍ，背景光抑制本领优于１０＾－４。     

光纤光栅调谐全光纤激光器

本文提出了一种利用光纤光栅作为调谐装置的可调谐全光纤激光器。实验结果表明：该调谐装置操作简便,性能稳定。激光器输出波长连续可调,输出波长复现性误差小于０．００８ｎｍ,输出功率大于１ｍＷ,激光谱线宽小于０．０１ｎｍ,波长调谐范围大于６．４ｎｍ。     

ErLaP_5O_（14）非晶上转换发光分析

测量了Ｅｒ０．１Ｌａ０．９Ｏ１４非晶在６４９．０ｎｍ脉冲染料激光泵浦下的上转换荧光谱线（５５２．２，５４５．７，５４２．９）ｎｍ，５２５．０ｎｍ．４６８．８ｎｍ，４５２．２ｎｍ．（４１１．２，４０７．０）ｎｍ，３８４．１ｎｍ．３８０．７ｎｍ，其中（５５２．２，５４５．７，５４２．９）ｎｍ，（４１１．２．４０７．０）ｎｍ．３８４．１ｎｍ话线是共振步进双光子吸收导致的，而４６８．８ｎｍ．４５２．２ｎｍ，３８０．７ｎｍ是三光子荧光。     

高隔离度偏振无关光环行器

本文报道了一种高隔离度偏振无关的三端口光环行器。该环行器在１．５５μｍ中心波长±２０ｎｍ范围内，插入损耗低于１ｄＢ，隔离度大于４５ｄＢ，偏振相关损耗低于０．２ｄＢ，串音大于５０ｄＢ，回波损耗大于５０ｄＢ。     

纳米硅／非晶硅多层膜室温可见光致发光研究

本文报道了在用等离子体增强化学汽相淀积法制备的氢化纳米硅（ｎｃ－Ｓｉ：Ｈ）／氢化非晶硅（ａ－Ｓｉ：Ｈ）多层膜中，未经任何后处理工艺，观察到室温可见光致发光（ＰＬ）．当ｎｃ－Ｓｉ：Ｈ层厚度由４．０ｎｍ下降至２．１ｎｍ时，ＰＬ峰波长由７５０ｎｍ兰移至７０８ｎｍ．本文将这种对量大于Ｓｉ单晶能隙的光发射归因于多层膜中ｎｃ－Ｓｉ：Ｈ子层的量子尺寸效应．     

高功率激光作用下多光子激发Cs_2的新扩散带辐射

本文报告当λ＝１．０７５６ｍ的强激光作用于铯金属蒸气时，获得了从波长４１０ｎｍ到４７３ｎｍ的准连续的新的辐射带，它在４１２．７ｎｍ、４２１．５ｎｍ、４３３．１ｎｍ、４４５．２ｎｍ、４４６．６ｎｍ及４６０．６ｎｍ等处有较高的强度，初步分析表明这个准连续辐射带是来源于Ｃｓ２的新扩散带，这是迄今首次获得的Ｃｓ２的一个新的谱带实验结果。     

掺饵光纤放大器用1480／1550nm波分复用器的优化设计

以组合波导理论为基础，分析了１４８０／１５５０ｎｍ波分复用器的耦合区横截面形状和尺寸与偏振灵敏度的关系。着重比较了矩形截面和椭圆形截面二种波分复用器的偏振性能，并发现当椭圆截面的短轴与长轴之比为１：１．８８时，器件性能几乎与偏振无关。研制成功的１４８０／１５５０ｎｍ波分复用器的波长隔离度大于２０ｄＢ．偏振灵敏度小于０．１ｄＢ．附加损耗小于０．５ｄＢ。     

利用1．313μm激光泵浦掺铒石英光纤产生上转换放大自发辐射

报道了利用１．３１３μｍ波长调Ｑ锁模Ｎｄ３＋：ＹＬＦ激光泵浦国产掺铒石英光纤同时产生可见光４６３ｎｍ（４６３ｎｍ，４７５ｎｍ，４８５ｎｍ，４９４ｎｍ，５０１ｎｍ，５１０ｎｍ），５２５ｎｍ，５４０ｎｍ（５２５～５６４ｎｍ），二次谐波信号６５６ｎｍ（６５６～６７５ｎｍ）和近红外８０４ｎｍ（７８４～８２０ｎｍ）等波段放大自发辐射的实验结果．在可见光４６３ｎｍ波段，在高泵浦功率下观察到随泵浦光功率增大，邻近几个中心波长与４６３ｎｍ波长信号产生类似级联共振放大增强的现象。同时发现几个中心波长辐射光谱宽度随泵浦光功率增加有加宽的关系，这与现有实验结果报道不一致。实验中还发现３ｍ长光纤与４．５ｍ长光纤在输出可见光自发辐射光谱方面有很大的不同．３ｍ光纤在相等泵浦光功率下．出现邻近波长共振放大加强的几率比４．５ｍ光纤小得多。根据能级跃迁关系提出了共振四光子吸收将基态４Ｉ１５／２离子抽运到高能态２Ｇ７／２，然后跃迁辐射回到４Ｉ１３／２态的机制，给出了实验结果的初步机理解释。     

SIOFM－5FW软X射线底片与Kodak101－05和Ilford－Q板曝光特性的比较

在相同的曝光和显影条件下，用Ｄ－１９和Ｐｈｅｎｉｓｏｌ两种显影液定性比较了ＳＩＯＦＭ－５ＦＷ底片、Ｋｏｄａｋ１０１－０５和Ｉｌｆｏｒｄ－Ｑ板在１００．０ｎｍ以下的软Ｘ射线和ＸＵＶ波段范围里的曝光特性．比较实验表明，ＳＩＯＰＭ－５ＦＷ底片对波长大于１０．０ｎｍ的辐射的响应介于Ｋｏｄａｋ１０１－０５和ＩＩｆｏｒｄ－Ｑ板之间；对于１０．０ｎｍ以下的短波长区，ＳＩＯＰＭ－５ＦＷ比Ｋｏｄａｋ１０１－０５灵敏，而且有较高的饱和光密度值和动态范围，但存在明显的碳Ｋ吸收边结构。讨论了所用的两种显影液对底片曝光特性的影响。     

激光合成纳米硅的可见发光

研究了激光ＣＶＤ合成纳米硅（平均粒径为１４ｎｍ）的可见发光特性。用３００－４５０ｎｍ波长激发时，在４００－６５０ｎｍ区间观测到了发射宽峰。首次发现粒径大于１０ｎｍ的纳米硅在室温下具有可见发光，该现象可用量子限制／发光中心模型来作定性解释。     

Current-Mode Temperature Compensated Continuous-Time CMOS Transconductance-C Filter

In this paper a low voltage low power current-mode continuous-timelow-pass filter is presented. The current-integrator is constructedof a multi-output linearized transconductance element drivenby a balanced transimpedance amplifier. A 1 MHz third order ellipticlow pass filter is designed and fabricated with the proposedcurrent-mode integrator. The measurements show capability ofoperation with down to a 3 V supply voltage. The measured currentconsumption is 850 µA at room temperature andthe dynamic range is 66 dB. The distortion of the filter is below50 dBc with peak signal levels up to twice the quiescent currentlevel and with the refined designs even lower distortion is expected.The filter uses a CMOS-current reference for temperature andprocess variation stabilization with a measured corner frequencytemperature coefficient of –100 ppm/K.     

宽带速调管滤波器加载输出腔间隙阻抗的频率特性的模拟计算方法

该文通过理论分析和推导建立起宽带速调管滤波器加载输出腔间隙阻抗的频率特性的模拟计算方法,同时,通过对实际问题的计算阐明了如何应用该方法确定加载输出腔的谐振频率和外观品质因数并对计算结果的合理性做了论证。最后通过滤波器加载输出腔的模拟计算结果与冷测结果的比较和分析,进一步验证该方法的可靠性。     

Efficient Beam‐Training Technique for Millimeter‐Wave Cellular Communications

In this paper, a beam ID preamble (BIDP) technique, where a beam ID is transmitted in the physical layer, is proposed for efficient beam training in millimeter‐wave cellular communication systems. To facilitate beam ID detection in a multicell environment with multiple beams, a BIDP is designed such that a beam ID is mapped onto a Zadoff–Chu sequence in association with its cell ID. By analyzing the correlation property of the BIDP, it is shown that multiple beams can be transmitted simultaneously with the proposed technique with minimal interbeam interference in a multicell environment, where beams have different time delays due to propagation delay or multipath channel delay. Through simulation with a spatial channel model, it is shown that the best beam pairs can be found with a significantly reduced processing time of beam training in the proposed technique.     

IRST系统的综合性被动测距算法研究

专门讨论综合性的IRST系统的被动测距公式。在若干相连观测时刻,远处的目标被假定为具有恒定辐射强度的点源。在此基础上,结合美国海军模型进行了三维运动分析,得出了一个综合性的被动测距公式,仿真分析表明其相对定位误差优于7％。相应的定位方案适用于海上匀速直线运动的目标模拟。     

单瓣近衍射极限输出的带外腔半导体激光器

实验研究了带外腔反馈注入的宽接触条形激光器，并用光线传输矩阵分析了该外腔结构。利用闪耀光栅及耦合输出反射镜对表面未镀增透膜的半导体激光器构成外腔，选择一定模式的激光反馈注入回激光器，从而限制了其他模式在半导体激光器内的振荡，压缩了激光器输出激光的光谱宽度。当激光器驱动电流为2．7倍阈值电流时，获得230mW输出功率，0．6nm谱宽，单瓣近衍射极限的激光输出。用一平面镜代替光栅作为外腔反射镜，获得了320mW输出功率，1．5nm谱宽的单瓣近衍射极限的激光输出。     

WDM中级联EDFA噪声积累和系统功率预算

对波分复用（ＷＤＭ）系统中级联ＥＤＦＡ噪声积累和系统功率预算进行了研究,认为累积噪声随着放大器的级数线性增长,而且还随着放大器级间损耗（增益）指数增长。系统总长度一定时,低增益、多级数比高增益、少级数方案有高得奖我的光信噪比（ＯＳＮＲ）。     

Crosstalk analysis for a CMOS gate driven inductively and capacitively coupled interconnects

This paper deals with crosstalk analysis of a CMOS driven capacitively and inductively coupled interconnect. The Alpha Power Law model of MOS transistor is used to represent a CMOS driver. This is combined with a transmission line-based coupled RLC model of interconnect to develop a composite model for analytical purpose. On this basis a transient analysis of crosstalk noise is carried out. Comparison of the analytical results with SPICE extracted results shows that the error involved is nominal.     

永磁包装相对论返波管振荡器实验研究

首先通过粒子模拟设计了一个X波段的低磁场返波管振荡器,得到功率为520MW、频率为7.9GHz的微波输出;然后根据模拟结果设计加工了一个磁场强度为0.46T的小型化永磁磁体;最后在加速器上对永磁包装返波管振荡器进行了实验研究。当电子能量为630keV、束流约为6.7kA时,返波管振荡器得到频率为8.0GHz、功率为510MW、脉冲半高宽约15ns的微波输出。     

Integrated on-chip 0.35 μm BiCMOS current-mode DC–DC buck converter

A current-mode DC–DC buck converter with a fully integrated power module is presented in this article. The converter is implemented using BiCMOS technology in amplifier and power MOSFET in a current sensor. The current sensor is realised by the power lateral double-diffused MOSFET with the aspect ratio much larger than that of a matched p-MOSFET. In addition, BiCMOS technology is applied in the error amplifier for an accurate current sensing and a fast transient response. The DC–DC converter is fabricated with 0.35?µm BiCMOS process. Experimental results show that the fully integrated converter operates at 1.3?MHz switching frequency with a supply voltage of 5?V. The output DC voltage is obtained as expected and the output ripple is controlled to be within 2% with a 30?µH off-chip inductor and 100?µF off-chip capacitor.     

一种结构新颖的微波高功率定向耦合器

介绍一种结构新颖的微波高功率定向耦合器.该耦合器主线采用波导结构承受功率大,副线采用同轴结构对外连接方便,耦合机构采用单个圆孔实现,整个耦合器设计巧妙,结构简单,便于加工,易于装配,不用调试,指标好,可靠性高,特别适用于高功率、弱耦合、双向取样的场合.