| Extending the Conventional Information Theory: Theory and Designs of Layered Partially Decodable Codes |
29-Jan-2009 |
5 pages |
| Authors:
Lizhong Zheng; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
 | This project is aimed at extending the conventional information theory, which is based on the idea of reliably transmitting all data bits through communication channels, by differentiating different types of data and providing different levels of error protections and thus allowing different parts of the data to be decoded at different nodes in the network. The main challenge addressed in this project is to develop new notions of partial information, ... |
|
| Advanced Plasma Etching of Complex Combinations of III-V Heterostructures |
28-Sep-2008 |
4 pages |
| Authors:
Erich P Ippen; Leslie A Kolodziejski; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The optoelectronic structures and devices, whose study will be enabled by the acquired research instrumentation, including ultra-broadband modulators, photonic crystal lasers, and very fast optical logic circuits, are of intense interest for future Air Force needs. The objective of the research instrumentation acquisition is to enhance the institution's ability to study III-V semiconductor materials and devices. An inductively-coupled plasma reactive-ion etcher will be acquired for sophisticated, on-site fabrication of photonic ... |
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| Quantum Computation with Superconducting Quantum Devices |
14 APR 2008 |
17 pages |
| Authors:
Terry P. Orlando; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| This project has experimentally characterized the coherent quantum nature of the superconducting persistent current qubits which were fabricated in the trilayer niobium technology. The quantum levels of these qubits have been mapped out using both standard microwave frequency spectroscopy as well as a new technique of amplitude spectroscopy. Important to the future implementation of these qubits for quantum computing applications is the demonstration of microwave sideband cooling of the qubits ... |
|
| Electromagnetic Models for UXO Detection and Classification in Permeable Soils |
17-Mar-2008 |
43 pages |
| Authors:
Kevin O'Neill; Beijia Zhang; Jin A Kong; Bae-Ian Wu; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Support Vector Machine (SVM) and neural networks (NN), are applied to classifying metallic objects according to size using the expansion coefficients of their magneto-quasistatic (MQS) response in the spheroidal coordinate system. The classified objects include homogeneous spheroids and composite metallic assemblages meant to resemble unexploded ordnance. An analytical model is used to generate the necessary training data for each learning method. SVM and NN are shown to be successful in ... |
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| Information Transmission and Entanglement Distribution Over Bosonic Channels |
MAR 2008 |
9 pages |
| Authors:
Jeffrey H. Shapiro; Stewart D. Personick; Saikat Guha; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| High-sensitivity photodetection systems have long been limited by noises of quantum-mechanical origin. Nevertheless, analyses and designs of optical communication systems have seldom employed fully quantum treatments. As a result, these works do not establish the ultimate limits on optical communication performance. This program established an inner bound on the capacity region for the Bosonic broadcast channel, and showed that this inner bound is in fact the capacity region if a ... |
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| Electromagnetic Models and Inversion Techniques for Multiple UXO Discrimination |
31-Dec-2007 |
23 pages |
| Authors:
Beijia Zhang; Jin A Kong; Bae-Ian Wu; Hongsheng Chen; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Recovery of buried unexploded ordnance (UXO) is very slow and expensive due to the high false alarm rate created by clutter. Electromagnetic induction (EMI) has been shown to be a promising technique for UXO detection and discrimination. We use the EMI response of buried targets to identify or classify them. Given that now a more complete model of the measurable response of a buried UXO is implemented, this study proceeds ... |
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| Femtosecond Optics: Advanced Devices and Ultrafast Phenomena |
31 MAY 2007 |
48 pages |
| Authors:
Erich P. Ippen; James G. Fujimoto; Franz Kaertner; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| OBJECTIVES: To investigate fundamental femtosecond-timescale phenomena in materials and devices. To evaluate the potential of these phenomena and structure for applications. To invent and demonstrate new devices for ultrafast optics. STATUS AND ACCOMPLISHMENTS: Over the three years of this program we have made significant achievements in several areas: development of new femtosecond laser systems and ultrafast optical techniques; application of ultrafast optics to waveguide and fiber devices; designs and studies ... |
|
| Few-cycle Optical Parametric Chirped Pulse Amplification |
08 JAN 2007 |
15 pages |
| Authors:
Franz X. Kaertner; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Over the last few years, ultrafast laser physics and frequency metrology has merged and provided us with unprecedented (sub-cycle) control over the electric field of few-cycle laser pulses emitted from modelocked lasers. These pulses and the corresponding technology are the prerequisite for high energy phase controlled few-cycle laser pulses, needed for reliable extreme ultraviolet (EUV) and soft x-ray production via high harmonic generation. It has been shown over the last ... |
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| Student Support for Quantum Computation With Superconducting Quantum Devices |
03 JAN 2005 |
7 pages |
| Authors:
Terry P. Orlando; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The research done by the graduate students on this grant focus on two topics: predominately, the focus was on the measurements of a persistent-current qubit driven by an on-chip radiation source, and secondarily on the fabrication of qubits for a fast turn around time. For the first topic the student preformed experiments of the monolithic integration of an onchip radiation source with a persistent-current (PC) qubit and dc SQUID measurement ... |
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| Long-Distance, High Data-Rate Quantum Communication With Ultralow Loss Photonic Band Gap Fiber |
11 AUG 2004 |
38 pages |
| Authors:
Yoel Fink; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| We are pleased to report substantial progress across the entire cylindrical photonic bandgap fiber project. This project's main objective is the development of ultra low-loss hollow photonic bandgap fibers for quantum communications applications. Specifically, the following objectives have been met: the worlds first automated preform fabrication system for low loss photonic bandgap fibers was specified, designed, ordered, manufactured and installed. This system will enable the fabrication of fibers with low ... |
|
| Strategic Applications of Ultra-Cold Atoms; MURI Fellowship for J.R. Abo-Shaeer |
14 JUN 2004 |
11 pages |
| Authors:
Wolfgang Ketterie; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The goal of the MURI project is to advance matter wave sensors by combining atom interferometry with atom lasers and atom waveguides. This has the prospect of improving the sensitivity of such sensors by orders of magnitude as compared with existing state-of-the-art sensors. This final report summarizes major steps towards this goal, including the study of wave guides using atom chips, the demonstration of the novel method of contrast interferometry ... |
|
| Sub-100nm, Maskless Deep-UV Zone-Plate Array Lithography |
07 MAY 2004 |
154 pages |
| Authors:
Harry I. Smith; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Semiconductor lithography is at a crossroads. With mask set costs in excess of $1M, long mask-turn-around times, and tools that are characterized by their inflexibility and skyrocketing costs (in excess of $20M), there is need for a new paradigm in lithography. Zone-Plate-Array Lithography (ZPAL) bypasses some of the most pressing problems of current lithography equipment by offering a maskless lithography tool that is scalable, flexible and low cost. It is ... |
|
| PBG Cavity in NV-Diamond for Large Scale Type II Quantum Computing |
22 APR 2004 |
32 pages |
| Authors:
Selim Shahriar; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The objective of this project was to investigating the feasibility of realizing a type II quantum computer (QC) on a large scale, using nitrogen- vacancy color centers in diamond (NV-Diamond). To see the basic mechanism behind this scheme, consider a small volume of this medium. A laser beam incident on this volume can interact with all the centers in this volume. However, each center has a transition frequency that is ... |
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| Feasibility of Spectral Holeburning Memories and Processors for Space- Based Applications |
22 APR 2004 |
38 pages |
| Authors:
Selim Shahriar; Shaoul Ezekiel; Cardinal Warde; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The purpose of this research was to explore the feasibility of using spectral hole-burning (SHB) memories for caching and processing large amounts of high-speed imagery data that are expected in future space-based surveillance systems. The research was to consist of three parts. First, the power of spectral holeburning for image-based storage and processing was to be illustrated by performing several demonstration experiments, using Raman excited spin coherence (RESC). Second, the ... |
|
| Femtosecond Photonics: Fundamental Phenomena and Advanced Devices |
12 APR 2004 |
52 pages |
| Authors:
Erich Ippen; Herman Haus; James Fujimoto; Franz Kaertner; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Ultrashort pulse laser technology is an active field of research that has had a powerful impact in many areas of science. Applications of ultrafast technology range from biomedical optical imaging such as optical coherence tomography (OCT), to high-speed communications, investigation of ultrafast nonlinear process in semiconductor materials and devices, optical frequency metrology, the design of optical clocks, and micro-machining. |
|
| Type II Quantum Computing With Superconductors |
01 APR 2004 |
17 pages |
| Authors:
Terry P. Orlando; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The results of this research centered on the experimental studies of a single superconducting persistent current qubit, the implementation of type-II algorithms using these qubits, and the proposal for adiabatic quantum computing using these qubits. The major experimental results on single superconducting persistent current qubits have been the observation of the quantum energy level crossings in niobium qubits, and the microwave measurements of intra-well relaxation times. We have developed two ... |
|
| Integrated Vacuum Growth System for Hybrid Organic-Inorganic Materials |
17 MAR 2004 |
13 pages |
| Authors:
Vladimir Bulovic; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Our recent demonstrations of efficient inorganic-quantum-dot light- emitting devices in molecular organic hosts indicate the vast potential of hybrid organic/inorganic nanostructured materials for development of practical active devices. Experience shows that essential to the high performance of such nano-structures is the high material purity and controlled device growth. Both can be improved through the use of the novel and versatile integrated materials deposition system developed in this program. |
|
| Sub-1nm Patterning Accuracy via Spatial-Phase Locking |
19 DEC 2003 |
35 pages |
| Authors:
Henry I. Smith; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Scanning-electron-beam lithography (SEBL) is an essential tool for creating patterns of arbitrary geometry at feature sizes below 100 nm, even down to 15 nm dimensions. Aside from the slow writing speed, the most outstanding problem of SEBL is its inability to achieve pattern-placement accuracy that is compatible with its resolution. For example, commercial SEBL systems, costing several millions of dollars, can under the most ideal conditions achieve placement accuracy of ... |
|
| Spike-Based Hybrid Computers |
02 OCT 2003 |
6 pages |
| Authors:
Rahul Sarpeshkar; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| This report documents progress made during the period July 1st 2002 to Jan 2003 for the ONR grant 'Spike-Based Hybrid Computers'. It is the fourth and final progress report for this grant. Our progress this year was in three areas: (1) Ultra-Low-Power Time-Based Analog-to-Digital Conversion inspired by neuronal signal representations; (2) An analog integrated circuit memory element for use in learning and adaptive systems, and (3) A predictive comparator with ... |
|
| Very Low Temperature Measurement System for Quantum Computation with Superconductors |
27 AUG 2003 |
7 pages |
| Authors:
Terry P. Orlando; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Two dilution refrigerators have been installed and made operational for the purpose of having dedicated measurement systems one at MIT and the other at the University of Rochester for carrying out quantum computing experiments. Both systems are a Kelvinox 400 model from Oxford instruments, equipped with both dc and rf lines for measurements; and both systems are vibrationally isolated and magnetically and electrically shielded for low noise measurements. Within the ... |
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| Advanced Optoelectronic Components for All-Optical Networks |
19 JUL 2002 |
19 pages |
| Authors:
Jeffrey H. Shapiro; Hermann A. Haus; Erich P. Ippen; Leslie A. Kolodziejski; Henry I. Smith; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Under APOSR Grant F49620-96-1-0126, 'Advanced Optoelectronic Components for All-Optical Networks', we have worked to develop key technologies and components to substantially improve the performance, and potentially lower the cost, of future optical networks. Our multidisciplinary team comprised MIT faculty and research staff whose collective expertise spans optical materials, optical component fabrication, ultrafast optics, optical communications, and network architecture. The specific objectives of our program were to: (1) develop key technology ... |
|
| Quantum Logic and Parallel Computing Using Spectral Holeburning Technologies |
04 JUN 2002 |
40 pages |
| Authors:
Selim Shahriar; Shaoul Ezekiel; Seth Lloyd; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The objective of this project was to investigate the use of spectral holeburning technologies for quantum logic and parallel computing. To this end, we have made substantial progress on both experimental and theoretical fronts. In NV-diamond, we have demonstrated the alignment of spins, which can then be used as quantum bits for a quantum computer. We have performed high resolution imaging of color centers in NV-diamond, as a key step ... |
|
| Quantum Computation With Mesoscopic Superconducting Devices |
15 MAY 2002 |
16 pages |
| Authors:
T. P. Orlando; J. E. Mooij; Seth Lloyd; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The goal of this research was to explore the use of superconducting circuits as components for quantum computing Quantum computers are devices that store information on quantum variables and process that information by making those variables interact in a way that preserves quantum coherence. Typically, these variables consist of two quantum states, and the quantum device is called a quantum bit or qubit Superconducting quantum circuits have been proposed as ... |
|
| New Developments in Atom Interferometry |
13 MAY 2002 |
9 pages |
| Authors:
David Pritchard; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| We have pioneered new measurement techniques using coherent atom optics (such as beam-splitters, mirrors and lenses) to manipulate matter waves. During this grant period we built an improved atom interferometer which splits deBroglie waves of matter into two physically separate paths and then recombines the waves to make interference hinges of matter. Using this apparatus our experiments are extremely sensitive to any forces on the atoms. |
|
| Joint Services Graduate Fellowship Program |
21 FEB 2002 |
19 pages |
| Authors:
Wolfgang Ketterle; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The graduate fellowship was first held by Dan Stamper-Kurn from October 1997 until his graduation on February 1, 2000 and then by Ananth Chikkatur from September 1, 2000 until October 14, 2001. The following papers were published by those two students during the time they were supported by the JSEP fellowship: |
|
| Femtosecond Photonics: Fundamental Phenomena and Advanced Devices |
31 DEC 2001 |
46 pages |
| Authors:
Erich P. Ippen; James G. Fujimoto; Hermann A. Haus; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| During the period of this program we made significant progress in several areas, in the development of new femtosecond lasers and techniques, in the application of ultrafast optics to fiber devices and to studies of novel materials and material structures. Some of these key advances are summarized in sections entitled: (1) Ultrashort pulse femtosecond lasers; (2) Optical phase and waveform control of sub-two-cycle pulses; (3) Dispersion managed propagation and modelocking; ... |
|
| Atom Interferometry |
27 DEC 2001 |
10 pages |
| Authors:
David E. Pritchard; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| We are developing new measurement techniques using coherent atom optics (such as beam-splitters, mirrors and lenses) to manipulate matter waves. We operate an atom interferometer, which splits deBroglie waves of matter into two physically separate paths and then recombines the waves to make interference fringes of matter. By measuring the contrast and phase of these interference fringes, our experiments are extremely sensitive to any interactions affecting the atoms. |
|
| Quantum Logic and Parallel Computing Using Spectral Holeburning Technologies |
OCT 2001 |
40 pages |
| Authors:
Selim Shahriar; Shaoul Ezekiel; Seth Lloyd; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The objective of this project was to investigate the use of spectral holeburning technologies for quantum logic and parallel computing. To this end, we have made substantial progress on both experimental and theoretical fronts. In NV-diamond, we have demonstrated the alignment of spins, which can then be used as quantum bits for a quantum computer. We have performed high resolution imaging of color centers in NV-diamond, as a key step ... |
|
| Training Spatial Knowledge Acquisition Using Virtual Environments |
23 APR 2001 |
8 pages |
| Authors:
Nathaniel Durlach; Thomas E. von Wiegand; Andrew Brooks; Lorraine Delhorne; Johnathon Pfautz; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| This report summarizes the work done by MIT in Year 5 (1 February 2000 through 31 January 2001) of the ONR Grant N00014-96-1-0937 entitled "Training Spatial Knowledge Acquisition Using Virtual Environments". It has been prepared by Nathaniel Durlach (PI), Dr Thomas E. v. Wiegand, Andrew Brooks, Lorraine Delhorne and Jonathan Pfautz. Much of our effort during this period has been directed towards further refinement and development of the generic spatial- ... |
|
| Atom Interferometry, Atom Optics and the Atom Laser |
FEB 2001 |
11 pages |
| Authors:
Wolfgang Ketterle; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Our goal is to pursue atom interferometry and advances of the atom laser using Bose-Einstein condensates. Condensates will be moved from a vacuum chamber where they were produced into a science chamber where a great variety of experiments can be carried out without the severe limitations imposed by the cooling and trapping techniques applied in the first chamber. The new chamber has been constructed, and first Bose-Einstein condensates were produced ... |
|
| Atom Wave Interferometers |
19 SEP 2000 |
16 pages |
| Authors:
David Pritchard; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Long-term research objective: Matter wave interferometers, in which de Broglie waves are coherently split and then recombined to produce interference fringes, have opened exciting new possibilities for precision and fundamental measurements with complex particles. The aim of our research program is to extend the ideas and techniques of atom optics and atom interferometry which underlie atom inteeferometers, to use these devices to make qualitatively new and/or more precise measurements in ... |
|
| Thermal Noise Behavior of the Bridge Circuit |
MAR 2000 |
40 pages |
| Authors:
Geoffrey J. Coram; Brian D. Anderson; Jr Wyatt John L.; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| This paper considers a connection between the deterministic and noisy behavior of nonlinear networks. Specifically, a particular bridge circuit is examined which has two possibly nonlinear energy storage elements. By proper choice of the constitutive relations for the network elements, the deterministic terminal behavior reduces to that of a single linear resistor. This reduction of the deterministic terminal behavior, in which a natural frequency of a linear circuit does not ... |
|
| Atom Wave Interferometers |
30 NOV 1999 |
6 pages |
| Authors:
David E. Pritchard; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Matter wave interferometers, in which de Broglie waves are coherently split and then recombined to produce interference fringes, have opened exciting new possibilities for precision and fundamental measurements with complex particles. The aim of our research program is to extend the ideas and techniques of atom optics and atom interferometry which underlie atom interferometers, to use these devices to make qualitatively new and/or more precise measurements in atomic physics, and ... |
|
| Applications of Porous Glass Based Thick Holograms for Optical Data Storage and Narrow-Band Wave Length Filtering |
SEP 1999 |
31 pages |
| Authors:
Shaoul Ezekiel; Selim Shahriar; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Under this grant, our objective was to test the feasibility of realizing holographic optical memory. |
|
| Studies of Optical Spectral Holeburning Using Raman Coherent Population Trapping |
31 JUL 1999 |
31 pages |
| Authors:
Shaoul Ezekiel; Selim Shahriar; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Under this grant, we have studied Raman coherent population trapping in a solid, with applications to five dimensional optical data storage. In particular, we have studied Raman spectral holeburning in Pr:YSO, which has properties suitable for optical data storage. During this period, we have made significant advances in our pursuit towards storage of optical information in this medium. In addition, we have stored and retrieved optical images in two amorphous ... |
|
| Experiments with Trapped Neutral Atoms |
15 JUL 1999 |
12 pages |
| Authors:
Wolfgang Ketterle; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Our long-term goals are twofold. First, to explore the new properties of gaseous Bose-Einstein condensates and advance our understanding of quantum gases. Second, we want to use Bose condensed gases as new atom sources of unprecedented brightness ("atom lasers") for precision atom optics and precision metrology. |
|
| Titanium Hydride Formation in Ti/Pt Films: the Impact on Ti/Pt/Au-gated III-V FETs |
22 JUN 1999 |
13 pages |
| Authors:
R. R. Blanchard; J. A. Del Alamo; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Ti/Pt metal layers are an integral part of the gate stack of many III-V field-effect transistors (FETs). These devices are known to be affected by H(sub 2) exposure. In this study, Auger Electron Spectroscopy (AES) measurements of Ti/Pt bilayers are correlated with electrical measurements of InAlAs/InGaAs/ InP FETs fabricated with Ti/Pt/Au gates. The PET measurements show that H(sub 2) exposure shifts the device threshold voltage through the piezoelectric effect. AES ... |
|
| A Framework for Non-Gaussian Signal Modeling and Estimation |
JUN 1999 |
240 pages |
| Authors:
Shawn M. Verbout; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| This thesis develops a new statistical framework for analyzing and processing stationary non-Gaussian signals. The proposed framework consists of a collection of mathematical techniques for modeling such signals as well as an associated collection of model-based algorithms for solving certain basic signal processing problems. Two inference problems commonly encountered in practice are given special consideration: (i) identification of the parameter values of a non-Gaussian signal source based on a clean ... |
|
| Optical Frequency Standard in Trapped Atomic Hydrogen |
30 APR 1999 |
3 pages |
| Authors:
Daniel Kleppner; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Our goal to improve the effectiveness of atom cooling by using radio- frequency evaporation was met early in the grant period, and we obtained temperatures and densities close to those needed for Bose-Einstein condensation. Consequently, we deferred our work on high resolution optical spectroscopy of hydrogen while we pursued BEC. We obtained BEC last June, using new spectroscopic methods to identify the onset of the transition and to characterize the ... |
|
| Quantum Chaos in Rydberg Atoms |
30 APR 1999 |
4 pages |
| Authors:
Daniel Kleppner; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| We have carried out a study of physics in the semiclassical regime. Recently we extended the technique of recurrence spectroscopy to the time domain. In separate experiment we investigated extending the semiclassical closed orbit theory to a process whose origin is entirely quantum mechanical: tunneling. We studied the continuum photoexcitation spectrum of Ryberg states of lithium in an electric field under conditions for which the escaping electron must tunnel through ... |
|
| Training Spatial Knowledge Acquisition Using Virtual Environments |
26 APR 1999 |
14 pages |
| Authors:
Nathaniel I. Durlach; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The purpose of this study is to explore the potential benefits of using current VE technology for training spatial orientation and navigation skills. |
|
| JSEP Fellowship |
04 JAN 1999 |
4 pages |
| Authors:
Erich Ippen; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| This fellowship supported Lynn Nelson until the completion of her PhDin 1997. The section below entitled "Modelocking of Thulium-doped and Erbium- doped Fiber Lasers" summarizes her research. For the remainder of the period, itsupported Erik Thoen in his SM research on "Ultrafast Gain-Index Coupling in InGaAsP Diode Lasers" and his PhD research on "Passive Modelocking of a Waveguide Laser with Semiconductor Saturable Absorbers." |
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| Multiscale Analysis and Control of Networks with Fractal Traffic |
OCT 1998 |
57 pages |
| Authors:
Warren M. Lam; Gregory W. Wornell; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| A recently-introduced multiscale framework is used to develop efficient analysis and design techniques for networks with self-similar traffic. These allow the interarrival density function for fractal point processes under Bernoulli random erasure to be determined, as well as the counting process distribution for superpositions of these processes. The results suggest that fractal characteristics are preserved under traffic branching and merging, which may, in turn, provide insight into the prevalence of ... |
|
| New Developments in Atom Interferometry |
31 JUL 1998 |
16 pages |
| Authors:
David Pritchard; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Atom interferometers have proven to be versatile tools, applicable in many different scientific and technical arenas. We have concentrated our efforts in the three major areas of precision measurements of important quantities in atomic physics, basic research into atom interferometric inertial sensors, and investigations of fundamental quantum mechanical principles. |
|
| Optical Phase Control of Ultrashort Femtosecond Pulse |
30 JUN 1998 |
5 pages |
| Authors:
Erich P. Ippen; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| When optical pulses achieve durations as short as a few optical cycles, their propagation and nonlinear interaction properties will begin to depend on the phase of the optical waveform relative to its envelope. We have recently demonstrated the feasibility of controlling the relative optical phase of successive pulses from a laser and propose here to study the effect of that control on the pulse formation process itself as well as ... |
|
| Fractal Point Process and Queueing Theory and Application to Communication Networks |
26 JUN 1998 |
6 pages |
| Authors:
Gregory W. Wornell; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| In the past year, our broad program of research has continued to explore efficient solutions fundamental problems of communication for wireless and wired networks, exploiting interrelated perspectives from communication theory, information theory, signal processing theory, control theory, and systems theory. As part of this work novel applications of fractal geometry, chaos, stochastic resonance, and other phenomena exhibited by nonlinear systems, are also being explored. |
|
| Numerical and Symbolic Algorithms for Application Specific Signal Processing |
01 MAY 1998 |
17 pages |
| Authors:
Alan V. Oppenheim; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| Our research under the RASSP program focussed on the development of new signal processing algorithms to exploit the advantages and opportunities of rapid prototyping for signal processing systems. Our work was carried out in the Research Laboratory of Electronics at MIT with close collaboration and interaction with industrial partners including Lockheed Sanders. Our primary accomplishments were in several categories. We developed and explored new classes of signals and algorithms related ... |
|
| Experiments with Trapped Neutral Atoms |
MAY 1998 |
15 pages |
| Authors:
Wolfgang Ketterle; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The program objectives are to develop an intensive source of Bose condensed sodium atoms and to study the properties of Bose-Einstein condensates. |
|
| MIT Microwiggler for Free Electron Laser Application. Non-perturbative Electron Beam Characterization with a Microwiggler |
25 FEB 98 |
145 pages |
| Authors:
Hermann A. Haus; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The potential of undulators to provide beam diagnostic information has been cited in the literature for many years. We demonstrate that while important parameters describing the beam - the energy, energy spread, divergence, spot size, matching and bunchlength - are convolved together in the synchrotron emission, a careful experimental setup can extract divergence, energy spread and bunchlength from this convolution. The MIT microwiggler is uniquely suited for the development and ... |
|
| Basic and Applied Research in the Field of Electronics and Communications |
18 FEB 1998 |
38 pages |
| Authors:
Jonathan Allen; MASSACHUSETTS INST OF TECH CAMBRIDGE RESEARCH LAB OF ELECTRONICS
|
| The MIT Research Laboratory of Electronics' Joint Services Program comprises seventeen work units (see below) that span a broad array of topics in high speed optics, surface and phase transitions, submicron structures and quantum effect devices, the electrical behavior of interconnect structures, and atomic and molecular physics. The work units include: (1) InGaAlAs Quantum Heterostructures for High Performance Devices; (2) Chemical Beam Epitaxy of II- VI/III-V Quantum Wells; (3) Physics ... |
|
Reports by Corporate Author
