检索结果-内蒙古大学图书馆

Optical Fiber Communication (OFC) Conference

作者： M.A. Popovic H.A. Haus M.R. Watts Department ofElectrical Engineering and Computer Science and the Research Laboratory ofElectronics Massachusetts Institute of Technology Cambridge MA USA

A hitless bypass switch for microphotonic channel add-drop filters that is based on /spl Delta//spl beta/ switches is described. We generalize the design to a large class of devices enabling variants of the switch and... 详细信息

关键词： Switching circuits Optical switches Optical filters Optical resonators Resonator filters Optical design Integrated optics Optical losses Photonics Optical devices

来源：评论

学校读者我要写书评

暂无评论

High Performance 1.45 μm InAs Quantum Dot Lasers on GaAs

High Performance 1.45 μm InAs Quantum Dot Lasers on GaAs

引用

Device Research Conference

作者： Z. Mi J. Yang P. Bhattacharya Solid-State Electronics Laboratory Department ofElectrical Engineering and Computer Science University of Michigan Ann Arbor MI USA

ISBN: (纸本)1424497495;0780397487

The conventional light source for long-haul optical communications has been InGaAsP/InP double heterostructure or multi-quantum well lasers, but these devices characteristically have high I{sub}(th), small T{sub}0 (40 - 50 K), small T{sub}1, and large values of chirp (≥ 2 A) and a-factor (～2 - 5). Two different material systems are being investigated for long wavelength lasers, both based on GaAs substrates. In the first, the active region consists of GaInNAsSb quantum wells and the lasers (λ ～1.45 - 1.6μm) are usually characterized by high J{sub}(th)(≥ 1000 A/cm{sup}2). The modulation characteristics are hitherto unknown. The other alternative is the use of In(Ga)As/GaAs quantum dots (QDs) as the gain material. While extraordinary performance has been reported for 1.3μm QD lasers (low I{sub}(th), T{sub}0 = ∞, α → 0, chirp < 1 A, f{sub}(-3dB) = 12 GHz), the development of 1.55μm QD lasers, wherein metamorphic QD heterosructures have to be used due to the large strain, has not been so optimistic. The devices reported (λ ～1.45μm) have J{sub}(th) ≥ 800 A/cm{sup}2, poor luminescence of the QDs with linewidth ≥ 70 meV and no data is available on the dynamic characteristics. By detailed investigation of the growth kinetics of the metamorphic heterostructures, we have realized InAs QDs on GaAs that are comparable in PL intensity and linewidth to state-of-the-art 1.1 and 1.3μm InAs QDs. 1.45μm lasers made with these heterostructures exhibit, for the first time, ultra low J{sub}(th) (70 A/cm{sup}2), T{sub}0 → ∞, f{sub}(-3dB) = 5 GHz, chirp ≤ 0.3 A, α ～1.0, and present a practical alternative to the InGaAsP/InP technology. The In{sub}0.15Ga{sub}0.85As/In{sub}0.15Al{sub}0.35Ga{sub}0.50As separate confinement heterostructure lasers with InAs QD active region, as illustrated in Fig. 1(a), were grown on (001) GaAs substrates by MBE. The active region consists of four or eight QD layers, which are either undoped or modulation doped p-type using Be (～20 holes per dot). A 0.6μm In{s

关键词： Quantum dot lasers Gallium arsenide Temperature Quantum well lasers Chirp Annealing Bandwidth Laser theory Solid lasers Indium phosphide

来源：评论

学校读者我要写书评

暂无评论

Decentralized Stabilization Control for Composite Systems with Time-Varying Delays and Uncertainties

Decentralized Stabilization Control for Composite Systems wi...

引用

International Conference on Information and Communication Technologies: From Theory to Applications, ICTTA

作者： Yuanwei Jing G.M. Dimirovski Institute of Control Science School of Information Science & Engineering Northeastern University Shenyang Liaoning China Institute of ASE Faculty ofElectrical Engineering Ss Cyril and Methodius University Skopje Macedonia Department of Computer Engineering Faculty of Engineering Acibadem Dogus University Istanbul Turkey

The stabilization problem of composite interconnected linear dynamic systems with delays and uncertainties in the plant interconnections and without is studied. Such a problem appears in the control of interconnected plant systems via networked interconnections. Conditions are derived when time-delays in the interconnections do not to impose difficulties to decentralized stabilization control of the interconnected plant provided the state vector is available. Main results of this contribution are given in terms of the respective theorems showing it is always feasible to stabilize the plant by designing appropriate local memoryless state feedback. An illustration example is given

关键词： Control systems Interconnected systems Time varying systems Delay systems Uncertainty Large-scale systems Power system dynamics Power system interconnection Asymptotic stability Reliability

来源：评论

学校读者我要写书评

暂无评论

Theory of Fermi Level Pinning of High-k Dielectrics

Theory of Fermi Level Pinning of High-k Dielectrics

引用

International Conference on Simulation of Semiconductor Processes and Devices (SISPAD)

作者： Kenji Shiraishi Yasushi Akasaka Naoto Umezawa Yasuo Nara Keisaku Yamada Hideki Takeuchi Heiji Watanabe Toyohiro Chikyow Tsu-jae King Liu University of Tsukuba Tsukuba Ibaraki Japan ATDF Inc. Austin TX USA Tokyo Electron Limited Tsukuba Ibaraki Japan Graduate School of Engineering Osaka University Suita Osaka Japan Advanced Electronic Materials Center National Institute for Materials and Science Tsukuba Ibaraki Japan Semiconductor Leading Edge Technologies Inc. Tsukuba Ibaraki Japan Department ofElectrical Engineering &Computer Science University of California Berkeley Berkeley CA USA Nanotechnology Laboratories Waseda University Shinjuku Tokyo Japan

Fermi-level pinning of poly-Si and metal-silicide gate materials on Hf-based gate dielectrics has been systematically studied theoretically. Fermi-level pinning in high-work-function materials is governed by the O vacancy generation and subsequent formation of interface dipoles near gate electrodes due to the electron transfer. On the other hand, O interstitial formation plays a crucial role for Fermi-level pinning in low-work-function materials. From our theoretical considerations, we have found that the work-function pinning-free-region generally appears due the difference in the mechanism of Fermi-level pinning of high- and low-work-function materials. The widening of this work-function pinning-free-region is the key issue for the fundamental relaxation of Fermi-level pinning in high-k gate dielectric

关键词： High-K gate dielectrics Hafnium oxide Electrons High K dielectric materials Dielectric materials Silicides Semiconductor materials Large scale integration Materials science and technology Lead compounds

来源：评论

学校读者我要写书评

暂无评论

Ultrahigh Resolution Endoscopic Optical Coherence Tomography

Ultrahigh Resolution Endoscopic Optical Coherence Tomography

引用

Photonics Asia 2004;Sensors and Imaging

作者： Paul R. Herz Pei-Lin Hsiung Aaron D. Auirre Hiroshi Mashimo Saleem Desai2 Macos Pedrosa2 Amada Koski Joseph Schmitt3 James G. Fujimoto' 'Department ofElectrical Engineering and Computer Science Massachusetts Institute ofTechnology Cambridge MA 02139 USA Saleem Desai2 Macos Pedrosa2 Amada Koski Joseph Schmitt3 James G. Fujimoto' 'Department ofElectrical Engineering and Computer Science Massachusetts Institute ofTechnology Cambridge MA 02139 USA Saleem Desai2 Macos Pedrosa2 Amada Koski Joseph Schmitt3 James G. Fujimoto' 'Department ofElectrical Engineering and Computer Science Massachusetts Institute ofTechnology Cambridge MA 02139 USA Veteran Administration Medical Center Harvard Medical School West Roxbury MA 02132 USA 3LightLab Imaging Inc. Westford MA 01886 USA

Early detection of gastrointestinal cancer is essential for the patient treatment and medical care. Endoscopically guided biopsy is currently the gold standard for the diagnosis of early esophageal ca

关键词： Optical Coherence Tomgoraphy, Endoscopy, Early Cancer Detection, Gastrointestinal Imaging.

来源：评论

学校读者我要写书评

暂无评论

A modest proposal: licensing personal computers and Internet service providers

A modest proposal: licensing personal computers and Internet...

引用

Proceedings of the Annual IEEE SMC Information Assurance Workshop (IAW)

作者： C. Ray Department ofElectrical Engineering and Computer Science United Stated Military Academy NY USA

As the threat to the Internet at large from poorly configured or maintained personal computers continues to increase it is increasingly important to consider ways to 'harden' these machines. By adopting a model based on the already familiar requirement for licensing and safety checks for individually owned vehicles operated on public thoroughfares, it may be possible to facilitate the public policy debate and gain mass acceptance in a relatively short span of time.

关键词： Proposals Licenses Microcomputers Web and internet services Personal communication networks computer crime Software maintenance Operating systems Vehicle safety Security

来源：评论

学校读者我要写书评

暂无评论

High speed, high resolution capable optical delay line for imaging transient biological function with optical coherence tomography

High speed, high resolution capable optical delay line for i...

引用

Conference on Lasers and Electro-Optics (CLEO)

作者： J.J. Reynolds D.L. Marks A.W. Schaefer S.A. Boppart Beckman Institute for Advanced Science and Technology Department ofElectrical and Computer Engineering University of Illinois Urbana-Champaign USA Beckman Institute for Advanced Science and Technology Department of Electrical and Computer Engineering UIUC USA

Summary form only given. We have developed a polygonal scanner based optical delay line that allows for potentially higher axial scan speeds than traditional linear or resonant galvanometers while supporting higher bandwidths. This type of delay line is based on designs used for signal autocorrelation measurement and demonstrated for OCT. In this type of optical delay line, a grating dispersed spectrum is focused onto a planar mirror with a controllable tilt angle. Implementation will be demonstrated by the in vivo OCT imaging of Xenopus laevis (African frog) tadpole cardiac function. This optical delay line has broad applicability in the fields of medicine and biology where both high resolution and high speed OCT are required.

关键词： Biomedical optical imaging High speed optical techniques Image resolution Delay lines High-resolution imaging Optical imaging Tomography Resonance Bandwidth Signal design

来源：评论

学校读者我要写书评

暂无评论

Self-switching fiber loops imbalance by fiber dispersion

Self-switching fiber loops imbalance by fiber dispersion

引用

Conference on Lasers and Electro-Optics (CLEO)

作者： W.S. Wong M. Margalit S. Namiki S. Longhi E.P. Ippen H.A. Haus Department ofElectrical Engineering and Computer Science and the Research Laboratory of Electronics Massachusetts Institute of Technology

来源：评论

学校读者我要写书评

暂无评论

A COLD INP-BASED TUNNELING INJECTION-LASER WITH GREATLY REDUCED AUGER RECOMBINATION AND TEMPERATURE-DEPENDENCE

引用

IEEE PHOTONICS TECHNOLOGY LETTERS 1995年第9期7卷 974-976页

作者： YOON, H GUTIERREZAITKEN, AL JAMBUNATHAN, R SINGH, J BHATTACHARYA, PK Electronics Laboratory Department ofElectrical Engineering and Computer Science University of Michigan Ann Arbor MI USA

We have measured the Auger recombination rates in an InP-based quantum well tunneling injection laser from large signal modulation experiments, Measured values of the Anger coefficient, C-a = 1.2 +/- 0.6 x 10(-29) cm(6)s(-1) at 283 K, are a factor of over 10(2) smaller than those measured in similar multiple quantum well separate confinement heterostructure lasers, In effect, the tunneling injection mechanism keeps the carriers ''cold'' even at high injection levels, A maximum value of T-o = 70 K is measured in the tunneling injection laser compared to 50 K for conventional quantum well structures.

关键词： Tunneling Radiative recombination Quantum well lasers Pump lasers Chemical lasers Laser theory Spontaneous emission Quantum well devices Waveguide lasers Pulse measurements

来源：评论

学校读者我要写书评

暂无评论

Spectral Analysis of Tissue Imaged with Ultrasound Sector Scanning

Spectral Analysis of Tissue Imaged with Ultrasound Sector Sc...

引用

IEEE Symposium (IUS) Ultrasonics

作者： C.D. Lapin B.J. Sullivan M.H. Paul Div of CardiologyChildren's Memorial Hospital Department ofElectrical Engineering h Computer Science Northwestern University Chicago IL USA

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：