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SPEAKER MEETING: Dr. Martin Fejer, Stanford University
LOCATION: TBA
OUTREACH ACTIVITY:
LOCATION: Martin Luther King Laboratory School
DEMONSTRATION OPEN HOUSE:
LOCATION: Northwestern University, Technological Institute, EG17
OUTREACH ACTIVITY:
LOCATION: East Prairie School
SEMINAR TOPIC: How Nonlinear Effects Shape Pulse Energy Fluctuations in Optical Fiber
SPEAKER: Dr. John Thompson DePaul University Department of Physics & Astronomy
LOCATION: ECE Conference Room (L324)
Snacks and refreshments will be served.
SEMINAR TOPIC: Noise Control in Fiber-Optic Lines
SPEAKER: Max Raginski Department of Electrical and Computer Engineering - Northwestern University
LOCATION: ECE Conference Room (L324)
Pizza and refreshments will be served.
OUTREACH ACTIVITY:
LOCATION: Chute Middle School
SEMINAR TOPIC: High and Very-High Resolution Optical and Ultra-Violet Spectroscopy to Study Interstellar Gas
SPEAKER: Dr. James Lauroesch Department of Physics & Astronomy - Northwestern University
LOCATION: ECE Conference Room (L324)
Pizza and refreshments will be served.
OUTREACH ACTIVITY:
LOCATION: Dawes School
OUTREACH ACTIVITY:
LOCATION: Haven Middle School
SEMINAR TOPIC: Optical Control of Electron Transfer Pathways: Strategies for Molecule-Based Electronics
SPEAKER: Prof. Michael R. Wasielewski Department of Chemistry - Northwestern University
LOCATION: ECE Conference Room (L324)
Pizza and refreshments will be served.
SEMINAR TOPIC: Electro-optic modulators based on new materials
SPEAKER: Seong-Soo Kim, Department of Physics and Astronomy, Northwestern University.
ABSTRACT: The field of communication industry is becoming increasingly more important due to social demand for exchange of the larger quantity of information. Optical communication has attracted many scientists and engineers because of the very high frequency of its carrier wave. This means its potential bandwidth is much broader than that of microwave communication. In order to take advantage of the broad bandwidth of light it is necessary to develop fast way of switching it. Electro-optical (EO) modulators based on three different materials are suggested. The goal of this research is the higher speed of modulation and the lower driving voltage. The three materials are BaTiO3, LiNbO3, and self-assembled chromophore. I will talk about the issues of EO modulators based on these three materials.
LOCATION: ECE Conference Room (L324)
Pizza and refreshments will be served.
We will also be holding the student chapter elections. There are many benefits from serving in leadership roles for the NU-OSA Student Chapter. For example, two of the past presidents have received New Focus Student Travel Grants to attend the OSA conferences.
SEMINAR TOPIC: Public lecture on Quantum Computing
SPEAKER: Professor Yuri Manin, Director of the Max-Planck Institute for Mathematics in Bonn, and the winner of the 1995 Nemmers Prize in Mathematics.
ABSTRACT: Quantum Computing is a rapidly expanding field which uses the laws of quantum mechanics to implement dramatically faster algorithms than are possible on a traditional computer; the talk will explore some of the subject's theoretical, practical and philosophical implications.
Manin's report on quantum computing for Séminaire Bourbaki in Paris.
A reception will precede the talk in Lunt 218 at 3.15pm. The lecture is jointly sponsored by the Mathematics, Electrical and Computer Engineering, and Physics Departments.
LOCATION: Annenberg Hall G15
SEMINAR TOPIC: Georgia Tech quantum computing project (Special Condensed Matter Seminar)
SPEAKER: Prof. Li You, Georgia Institute of Technology.
ABSTRACT: The relationship between computation and quantum theory was first discussed by Finkelstein, Benioff, and Feynman. The notion of a quantum computer was later proposed by Deutsch. The possibility that quantum mechanical computers might efficiently solve problems that are intractable for classical computers, first hinted at by Feynman, was demonstrated by Bernstein and Vazirani in 1993. In 1994 the computer scientist Shor proposed a new quantum algorithm for the factorization of large numbers into prime factors. This revolutionary development provided the first concrete example that quantum computation may have an efficiency far exceeding that of modern computers. Since that time an explosion of interdisciplinary activity in computer science and physics has resulted in numerous theoretical and experimental proposals. While the prospects for large scale integration of quantum logical gates may lie beyond current technology, recent development in the field of atomic, molecular, and optical physics have already received significant attention. At Georgia Tech, a major theoretical/experimental collaboration has started on implementing a quantum computer based on cavity QED systems and laser trapped and cooled atomic arrays. Our system has the potential for scale up and seems to preserve coherence well. I will discuss the major ideas and report our latest experimental and theoretical progress. I will also discuss another recent proposal from our collaboration where magnetic dipole interactions from trapped atomic arrays provide the necessary two-body interaction for entanglement creation/manipulation.
LOCATION: Tech LR4
The report about the meeting can be found here.
(Note the new date!!)
REGIONAL MEETING OF OSA STUDENT CHAPTERS
LOCATION: Tech M345
We will be visited by the OSA Chapter of Purdue University and, possibly, by representatives from other schools. Our meeting will help to make us familiar with what other optics groups are doing and promote our own research achievements, as well as provide an informal atmosphere for sharing student and professional experiences. This is the second meeting in the series; the first one was held in Purdue 3 years ago.
The tentative program includes a number of 5-10 min talks about projects pursued in different research groups, poster boards in the hallway for more detailed description of the projects, tour of Northwestern lab facilities, sharing student chapter experiences (e.g. educational outreach, collaboration), etc.
Everyone working or interested in the field of optics is welcome to attend.
Pizza and refreshments will be served.
Watch this site for updated information.
SPONSORS:
Optical Society of America,
Department of Electrical and Computer Engineering
For more information: contact Michael Vasilyev, Principal Organizer, vasilyev@ece.nwu.edu
SEMINAR TOPIC: Microcavity Enhanced Linear and Nonlinear Optical Processes
SPEAKER: Professor Hui Cao, Department of Physics and Astronomy, Northwestern University.
ABSTRACT: Microcavities have been used to modify the electromagnetic field distribution and thus control the light-matter interaction. In a high Q semiconductor microcavity, the spontaneous emission process of quantum well excitons becomes reversible, leading to Rabi oscillation. In a polymer-embedded microcavity, the second harmonic generation is greatly enhanced.
LOCATION: ECE Conference Room (L324)
Pizza and refreshments will be served.
We will also discuss our plans on hosting a regional Student Chapter meeting this November. We will be visited by the OSA Chapter of Purdue University and, possibly, by representatives from other schools, too.
OPTICS OUTREACH: Haven Middle School, Evanston, IL
NWU-OSA Student Chapter visited Haven Middle School located in Evanston, IL. We used two classrooms to set up demonstrations in one of them and to provide the hands-on optical activity in the other. About 120 students, 4 demonstrators from NWU-OSA Student Chapter, and 3 science teachers were involved.
We explained the concepts of reflection and refraction, total internal reflection, optical fibers, and their use in optical communication. By using hands-on activity materials from OSA Optics Discovery Kit and watching a number of our home-built demonstrations, the students learned about polarization, lens magnification, telescope, etc. The most impressive demonstrations, from the students point of view, were our home-built optical link between CD player and the speakers, and the fish-tank imitation of the optical fiber, where the light propagates in a water stream coming out of a small hole in the fish tank. We hope that this event excites the students interest in science.
SEMINAR TOPIC: FDTD Computational Electromagnetics Analysis of a Pulsed Microwave Confocal System for Early-Stage Detection of Breast Cancer.
SPEAKER: Susan C. Hagness, Computational Electromagnetics Laboratory, Department of Electrical and Computer Engineering, Northwestern University.
ABSTRACT: The finite-difference time-domain (FDTD) method of solving Maxwell's equations has become one of the most powerful tools for analyzing complex problems in electromagnetics. In this talk, I will present results from an FDTD analysis and feasibility study of a novel focused wideband microwave system for detecting early-stage breast cancer. In contrast to X-ray and ultrasound modalities, this method exploits the breast-tissue physical properties unique to the microwave spectrum. The system uses a coherent-addition antenna array with time-gating to enhance the detection of tumors while suppressing the effects of tissue heterogeneity and absorption. FDTD simulations show that tumors as small as 2 mm in diameter can be robustly detected in the presence of the background clutter generated by the heterogeneity of the surrounding normal tissue. An optimized ultrawideband bow-tie antenna element has been designed for this system using full-wave three-dimensional simulations.
LOCATION: ECE Conference Room (L324)
Pizza and refreshments will be served.
SEMINAR TOPIC: Optical properties of erbium-doped barium titanate thin films.
SPEAKER: Andrew Teren, Materials Science and Engineering Department, Northwestern University.
ABSTRACT: The success of Er-doped fiber amplifiers for applications in telecommunications has also stimulated a growing interest in Er-doped integrated optical amplifiers and lasers. Increased functionality can be attained by using electro-optic host materials for incorporating Er and other rare earths. While there has been significant progress in rare-earth doped bulk ferroelectric waveguide devices, thin films have only recently been explored. Our group is currently investigating Er-doped BaTiO3 thin films prepared by MOCVD for planar active devices. We have found this material to be a promising candidate for a thin film optical amplifier due to the high solubility (10^21/cm3) of erbium ions and the high optical efficiency of the luminescence emission at 1.5 microns.
LOCATION: ECE Conference Room (L324)
Pizza and refreshments will be served. We will also be holding student chapter elections.
SEMINAR TOPIC: Native Oxide of Al Bearing III-V Compounds
SPEAKER: Jonathan J. Wierer, Research Assistant, Solid State Devices Laboratory, Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign
ABSTRACT: Until recently, III-V compound devices with high Al composition were unreliable due to the extremely reactive nature of Al to H20 in air. While studying this issue in 1990, Holonyak and coworkers discovered stable, device-quality, insulating AlxGa(1-x)As native oxides. These oxides are formed by exposing high gap AlxGa1-xAs (or other high Al composition compounds) to H2O vapor (N2 carrier gas) at elevated temperatures (< 400 C). Since then Holonyak's group has demonstrated many applications for the native oxide technology including: electrical and optical confinement in quantum well heterostructure lasers, masking of impurity diffusion, reliability in commercial LED's, MOSFET structures, and VCSEL's. This talk will be a historical perspective of work on the Al oxide for the past 7 years.
LOCATION: ECE Conference Room (L324)
Pizza will be served.
SEMINAR TOPIC: Laser Tissue Welding: An alternative method of skin closure
SPEAKER: Nathaniel Fried, graduate student in the Biomedical Engineering Department, Northwestern University
ABSTRACT: The use of lasers for tissue closure represents a potential alternative to conventional mechanical means of tissue closure, such as sutures. Advantages of laser welding may include faster operative repair of wounds, accelerated wound healing, watertight closure, reduced probability of infection, and improved cosmetic results. This presentation will focus on the application of skin closure. A brief introduction to the history and applications of tissue welding will be discussed. It will then be shown how theories from tissue optics can be applied to laser welding to improve both weld strengths and cosmetic results.
LOCATION: ECE Conference Room (L324)
Refreshments will be served.
SEMINAR TOPIC: GaN and related compounds: materials, characterization, and devices
SPEAKER: Patrick Kung, Graduate Student in the Center for Quantum Devices, Northwestern University
LOCATION: Tech Room L324
Pizza and other refreshments will be served.
SEMINAR TOPIC: New Approaches for High Data Rate Optical Fiber Transmission: 100 Gbits/sec and Beyond
SPEAKER: Curtis R. Menyuk, Ph.D., Computer Science and Electrical Engineering, University of Maryland Baltimore County
ABSTRACT: The invention of the erbium-doped optical fiber amplifier, by eliminating the need for repeaters, has made possible a leap in transmitted data rates from 100 Mbits/sec to 100 Gbits/sec in just one decade. In today's systems, fiber transmission effects due to nonlinearity, chromatic dispersion, and randomly varying birefringence limit the transmission rates and distances. Innovative new approaches to overcoming these limits using dispersion management, phase and amplitude modulation, and signal processing will be presented.
LOCATION: Tech Room L324
OPTICS OUTREACH: Fenger Academy, Chicago, IL
The NWU-OSA Student Chapter presented demonstrations to 3 electronics classes and 2 physics classes comprised of juniors and seniors at the Fenger Academy on the far south side of Chicago.
In the electronics classes, we talked about communications, both optical and electronic. We demonstrated the optical link -- a free-space LED-driven CD player -- designed by Glenn Bartolini and Greg Kanter. In the physics classes, we talked about the fundamental properties of light and used the OSA optics kits.
The goal of this outreach program is to spread awareness of optics to high school students. To motivate an interest in science, we provide hands-on experiments and try to relate the physics to the students' daily lives.
SEMINAR TOPIC: Cavity QED of Excitons in Semiconductor Nanostructures
SPEAKER: Dr. Hailin Wang, Department of Physics, University of Oregon
ABSTRACT: Cavity QED concerns about quantitative as well as qualitative changes in the dynamics of optical interactions due to the presence of a microresonator or due to the quantization of electromagnetic mode densities. Although cavity QED is traditionally pursued with simple atomic systems, recent advances in the fabrication of semiconductor nanostructures hpe opened the door to cavity QED studies of semiconductors.
In this talk, I will describe our recent progress on cavity QED of quasi-two dimensional excitons in quantum well structures. Specifically, I will discuss spontaneous emission process of excitons in a quantum well, normal mode excitations (cavity-polaritons) of excitons coupling strongly to a single electromagnetic modes, and possibilities of realizing a non-equilibrium condensation of cavity- polaritons. Future directions of cavity QED of semiconductor nanostructures will also be discussed.
Prof. Hailin Wang has done extensive works in the studies of quantum confined structures using state- of-the art femtosecond optical measurement techniques, including: study of bi-excitons, carrier dependent bandgap renormalization, photon echoes from localized and delocalized states in GaAs quantum wells, phonon-assisted migration of localized excitons in quantum wells, study of heavy-hole excitons, and measurement of Zeeman splitting in quantum wells. Recently, he is studying the effects of microcavities on exciton emission dynamics.
LOCATION: Tech Room L324
SEMINAR TOPIC: Amplitude squeezing by means of quasi-phasematched second-harmonic generation in a lithium niobate waveguide
SPEAKER: Darwin Serkland, Post-doctoral Fellow, Department of Electrical and Computer Engineering, Northwestern University
ABSTRACT: Traveling-wave second-harmonic generation is theoretically expected to produce amplitude-squeezed light at both the fundamental and second-harmonic frequencies. We have observed such squeezing by frequency doubling 1.5-micron mode-locked pulses using a lithium niobate waveguide. The measurements of squeezing versus conversion efficiency agree reasonably well with theory.
LOCATION: Tech Room L324
Pizza and beverages!
NWU-OSA Student Chapter elections!!! We will be electing a new president
(or co-presidents), secretary/webmaster, and treasurer for 1997.
SEMINAR TOPIC: Demonstration of All-Optical Storage of Picosecond Pulse Packets
SPEAKER: Glenn Bartolini, PhD Candidate, Department of Electrical and Computer Engineering, Northwestern University
ABSTRACT: Ultrahigh-speed time-division multiplexed optical networks will require all-optical buffers for many functions such as packet identification, demultiplexing, and collision avoidance. Experiments to demonstrate long-term storage of soliton packets, including loading and unloading schemes, using a phase-sensitive amplifier within a fiber resonator will be discussed.
LOCATION: Tech Room L324
Pizza and beverages will be provided!
We will also talk about upcoming outreach activities and student
chapter elections.
OPTICS OUTREACH: New Student Orientation
The Electrical and Computer Engineering department held an orientation session for new students before the opening of the school year. To promote our OSA student chapter and optics at Northwestern, Glenn Bartolini organized a set of optics demonstrations as part of our ongoing OSA outreach programs. The "tour" included demonstrations of fiber optics, interferometry, and holography.
SEMINAR TOPIC: Nonlinearities in Semiconductors and Their Use in Information Processing
SPEAKER: Elsa Garmire, Dean and Professor, Thayer School of Engineering, Dartmouth College
LOCATION: Tech Room L324