Oklahoma State Physics Department Seminars and Colloquia August through December, 1994 (updated October 21, 1994) ------------------------------------------ ------------------------------------------ Seminars and Colloquia, Typical Week: ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Date: Thursday Time: 1:30 PM Place: Classroom Building, Room 106 Inquiries: physmas@mvs.ucc.okstate.edu physsna@mvs.ucc.okstate.edu ------------------------------------------ Physics Colloquium: Date: Thursday Time: 3:30 PM Place: PS 110 Inquiries: jhhp@jperk.phy.okstate.edu ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Date: Friday Time: 2:00 PM Place: PS 147 Inquiries: jhhp@jperk.phy.okstate.edu ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, August 22-26, 1994 ------------------------------------------ Physics Colloquium: Speaker: Dr. Michael A. Stroscio Director, U.S. Army Research Office Date: Thursday, August 25 Time: 3:30 PM Place: PS 110 Title: Confined and Interface Optical and Acoustic Phonons in Quantum Wells and Quantum Wires Refreshments served at 2:45 PM, 4th Floor of Noble Research Center (Welcome Get-together) ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, August 29-September 2, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Speaker: Dr. Patrick Skubic University of Oklahoma Date: Thursday, September 1, 1994 Time: 1:30 PM Place: Classroom Building, Room 106 Title: Highlights of DPF 1994 ------------------------------------------ Physics Colloquium: Speaker: Dr. Jacques H. H. Perk Department of Physics, OSU Date: Thursday, September 1, 1994 Time: 3:30 PM Place: PS 110 Title: Star-Triangle Equations for Pedestrians Refreshments served before Colloquium in Physical Sciences, Room 147, at 3:00 PM, where also the traditional student-speaker informal discussion is scheduled 2:45-3:15. Abstract: Star-Triangle Equations were first introduced in 1899 to understand questions about the design of electric power generators and Wheatstone bridges. They provide a powerful simple algorithm for calculations in linear electric networks. In the twenties such algorithms were also introduced as Reidemeister moves in the mathematical theory of knots. In 1944 they appeared for the first time in statistical mechanics and in 1964 in quantum field theory. Now they are commonly known as Yang-Baxter Equations and are widely used in mathematics and physics, especially when there is an underlying "quantum group," or "solitons" in the classical limit. In this talk, we shall discuss principles and applications with a minimum of mathematics. ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, September 5-9, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Not scheduled ------------------------------------------ Physics Colloquium: Speaker: Dr. James P. Wicksted Department of Physics, OSU Date: Thursday, September 8, 1994 Time: 3:30 PM Place: PS 110 Title: Raman Spectroscopic Studies of Metabolic Concentrations in Aqueous Solutions Refreshments served before Colloquium in Physical Sciences, Room 147, at 3:00 PM, where also the traditional student-speaker informal discussion is scheduled 2:45-3:15. Abstract: Individual concentrations of glucose, lactic acid, and urea down to 0.1 wt. % have been investigated in aqueous solutions using the Raman scattering technique. These measurements have been conducted using several different laser wavelengths in conjunction with a grating spectrometer and a liquid nitrogen cooled CCD. Rabbit and human aqueous humor specimens were also studied whereby Raman structure similar to the stretching vibrational modes of methylene and methyl groups, associated with glucose and lactate, were observed. The potential application of this technique for measuring, in vivo, metabolic concentrations within the eye will be discussed. ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Speaker: Sheng Xu Department of Physics, OSU Date: Friday, September 9, 1994 Time: 2:00 PM Place: PS 147 Title: Theoretical Study of Off-Center D^0 and D^- States in Quantum Wells ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, September 12-16, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Speaker: Dr. Satya Nandi Department of Physics, OSU Date: Thursday, September 15, 1994 Time: 1:30 PM Place: Classroom Building, Room 106 Title: Top Quark Dynamics ------------------------------------------ Physics Colloquium: Speaker: Dr. H. M. Badran Department of Physics, OSU, and Tanta University (Egypt) Date: Thursday, September 15, 1994 Time: 3:30 PM Place: PS 110 Title: Ultra-High Energy Gamma Ray Astronomy Refreshments served before Colloquium in Physical Sciences, Room 147, at 3:00 PM, where also the traditional student-speaker informal discussion is scheduled 2:45-3:15. Abstract: Although cosmic rays were discovered as early as 1912 through the balloon flights of Hess (1912) which led to establish that cosmic rays originate outside the Earth's atmosphere, they still pose many unanswered questions, especially about their nature at high energies and their origin. In fact, even their name, cosmic rays, is a misnomer because the entities themselves are not 'rays' on the whole; they are nuclei of various kinds, rather than electromagnetic waves. Observations of cosmic rays are grouped into three categories: energy spectrum, mass composition, and anisotropy. Only recently, the first identification of a cosmic ray source in ultra high energy (>10^15 eV) has been achieved by the Kiel group [Samorski & Stamm, Ap. J. Lett., 268, L17, 1983], through their detection that Cyg X-3 emits pulsed gamma-rays. Since this identification many new arrays with improving angular resolution have been built or are under construction to identify the sources of Ultra High Energy radiation and to study the nature of the interaction of this radiation with matter. One of the most important new experiments is the HEGRA (High Energy Gamma Ray Array) air shower array, which is located on the top of the Roque de los Muchachos at the Canary Island La Palma, Spain. ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Not Scheduled ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, September 19-23, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Cancelled ------------------------------------------ Physics Colloquium: Speaker: Dr. Timothy M. Wilson Department of Physics, OSU Date: Thursday, September 22, 1994 Time: 3:30 PM Place: PS 110 Title: Site Dependence of the Electronic Structure of 3d Transition Row Substitutional Impurities in Ionic Crystals Refreshments served before Colloquium in Physical Sciences, Room 147, at 3:00 PM, where also the traditional student-speaker informal discussion is scheduled 2:45-3:15. Abstract: Transition metals in general are an important class of impurities in ionic insulators and semiconductors. The 3d ion substitutional impurities form deep trap levels and have open 3d shell configurations which are characterized by intra-center d->d optical transitions between atomic-like core states that are perturbed by the crystal field arising form the surrounding lattice. The transition metals in general often exhibit variable valency when acting as substitutional impurities. The results of Multiconfigurational SCF calculations for CaF_2:Mn and alpha-SiO_2:Fe will be used to show the important differences in the electronic structure of octahedrally and tetrahedrally bonded substitutional 3d ions. ------------------------------------------ Special Colloquium on Nonlinear Optics: Speaker: Dr. Nickolai V. Kukhtarev Alabama A&M University Huntsville, Alabama Date: Friday, September 23, 1994 Time: 1:30 PM Place: Noble Research Center, Room 107 Title: Nonlinear Optics of Photorefractive Materials: Physics & Applications Topics to be discussed include: Channeling of light by phase gratings, visualization of the IR images, photo-EPR, hexagonal scattering in KNbO_3:Fe, and the use of photorefractive materials for dynamic holography and optical data storage. ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Postponed one week, because of Special Colloquium on Nonlinear Optics ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, September 26-30, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Speaker: Dr. Mark A. Samuel Department of Physics, OSU Date: Thursday, September 29, 1994 Time: 1:30 PM Place: Classroom Building, Room 106 Title: Estimating Coefficients in PQFT --- An Update ------------------------------------------ Physics Colloquium: Speaker: Dr. Peter O. Shull Department of Physics, OSU Date: Thursday, September 29, 1994 Time: 3:30 PM Place: PS 110 Title: Advanced Placement Physics by Satellite, or The Mysteries of PS 151 Refreshments served before Colloquium in Physical Sciences, Room 147, at 3:00 PM, where also the traditional student-speaker informal discussion is scheduled 2:45-3:15. Abstract: AP Physics by Satellite is beamed live from OSU's campus television studios to high schools situated everywhere from Alaska to Massachusetts. Now in its ninth year, this comprehensive course in algebra-based physics has reached 5000 students. I will describe the course, its effectiveness, and the insights it provides into American schools today. ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Speaker: Dr. Wei Shan Department of Physics, OSU Date: Friday, September 30, 1994 Time: 2:00 PM Place: PS 147 Title: Study of Properties of Semiconductors under High Pressure ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, October 3-7, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Cancelled ------------------------------------------ Physics Colloquium: OSU Fall Break Weekend ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Speaker: Dr. Sergey V. Kravchenko Department of Physics, OU Date: Friday, October 7, 1994 Time: 2:00 PM Place: PS 147 Title: Metal/insulator transition in two dimensions at zero magnetic field ? ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, October 10-14, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Cancelled! ------------------------------------------ Physics Colloquium: Speaker: Dr. William D. Cochran McDonald Observatory University of Texas at Austin Date: Thursday, October 13, 1994 Time: 3:30 PM Place: PS 110 Title: The Great Train Wreck: The Impact of the Comet Shoemaker-Levy 9 on Jupiter Refreshments served before Colloquium in Physical Sciences, Room 147, at 3:00 PM, where also the traditional student-speaker informal discussion is scheduled 2:45-3:15. ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Speaker: Dr. Jin Fu Zhou Department of Physics, OSU Date: Friday, October 14, 1994 Time: 2:00 PM Place: PS 147 Title: Aggregation of Indocyanine Green ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, October 17-21, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Speaker: Dr. Per Bak Brookhaven National Laboratory Date: Thursday, October 20, 1994 Time: 1:30 PM Place: Classroom Building, Room 106 Title: Self-Organized Criticality ------------------------------------------ Physics Colloquium: Speaker: Dr. Kieran Mullen Department of Physics, OU Date: Thursday, October 20, 1994 Time: 3:30 PM Place: PS 110 Title: Superhexatics: The Spatial Ordering of Helium in Superfluid Films POSTPONED! Refreshments served before Colloquium in Physical Sciences, Room 147, at 3:00 PM, where also the traditional student-speaker informal discussion is scheduled 2:45-3:15. Abstract: Helium films have been a source of interesting physics, including two-dimensional melting, wetting phenomena, and superfluidity. Although one of the simplest systems, it still contains new surprises. Recent experiments on superfluid films have shown a variety of unexpected behaviors, such as submonolayer superfluidity and anomalous phase transistions. These experiments have prompted theories of new, highly ordered, superfluid states, such vortex-antivortex lattices and superhexatics. This colloquium will discuss some of the new physics of helium films, review the Kosterlitz-Thouless (KT) theory of two-dimensional melting, and finally discuss how KT theory might be generalized to cover recent experiments. ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Speaker: Dr. Xincheng Xie Department of Physics, OSU Date: Friday, October 21, 1994 Time: 2:00 PM Place: PS 147 Title: Electron Localization in a 2D System with Random Magnetic Flux ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, October 24-28, 1994 ------------------------------------------ Special Chemistry and Physics Seminar: Speaker: Dr. Janos Ladik Lehrstuhl fur Theoretische Chemie, University of Erlangen at Nuremberg Date: Tuesday, October 25, 1994 Time: 3:30 PM Place: Noble Research Center, Room 108 Title: Theory of Non-Linear Optical Properties of Polymers Coffee and cookies 3:00-3:30 4th floor NRC. ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Speaker: Dr. Doug McKay University of Kansas Date: Thursday, October 27, 1994 Time: 1:30 PM Place: Classroom Building, Room 106 Title: Gauge-Coupling and the Minimal SUSY Model: The Fourth Generation Below the Top? ------------------------------------------ Physics Colloquium: Speaker: Dr. Krishan K. Bajaj Dept. of Physics, Emory University Date: Thursday, October 27, 1994 Time: 3:30 PM Place: PS 110 Title: Excitons in Semiconductor Quantum Confined Structures Refreshments served before Colloquium in Physical Sciences, Room 147, at 3:00 PM, where also the traditional student-speaker informal discussion is scheduled 2:45-3:15. Abstract: In this talk we will review the properties of excitons in semiconductor quantum confined structures such as quantum wells, wires and dots in the presence of applied electric and magnetic fields. We will briefly describe the results of recent calculations of exciton binding energies and oscillator strengths and compare them with the available experimental data. Application of some of these studies to opto-electronic devices will be discussed. ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Not scheduled in view of Tuesday talk. ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, October 31-November 4, 1994 ------------------------------------------ Special Chemistry and Physics Seminar: Speaker: Dr. Dale W. Schaefer Sandia National Laboratory and U.S. Department of Energy Date: Tuesday, November 1, 1994 Time: 3:30 PM Place: Noble Research Center, Room 108 Title: New Routes to Nanostructure Materials: Microphase Separation Coffee and cookies 3:00-3:30 PM in NRC Room 207 (Foyer). Dr. Schaefer's principal research interests are colloids, polymers, and composite materials. A current special interest is the structure and properties of hybrid inorganic-organic polymeric materials, which he studies extensively by scattering techniques. ------------------------------------------ Special Physics Colloquium: Speaker: Dr. Nicolaas Bloembergen Nobel Prize Winner in 1981 Date: Wednesday, November 2, 1994 Time: 3:00 PM Place: Noble Research Center, Room 106 Title: Science and Society in the 21st Century Refreshments served before Colloquium on 4th Floor of Noble Research Center, at 2:00 PM. Reception in Suite 1600 of the Student Union, 5:00 PM - 7:00 PM. Abstract: The largest scientific and technological issues facing mankind include human population growth rate, decrease of biological diversity, quality of the atmosphere, oceans, and forests, and disarmament. Positive and negative influences of technological developments will be discussed. ------------------------------------------ Special Physics Colloquium: Speaker: Dr. Nicolaas Bloembergen Nobel Prize Winner in 1981 Date: Thursday, November 3, 1994 Time: 10:00 AM Place: Center for International Trade Development (CITD), Room 110 Title: Laser-Material Interactions: Fundamentals and Applications Abstract: The interaction of light with matter leads to electronic excitation by the absorption of photons. A large fraction of the high excitation energy of the electrons is transformed into heat on a time scale of about one picosecond in many circumstances. With lasers, power flux densities or intensities exceeding a terawatt/cm^2 are readily achieved and any material may be converted into a high temperature plasma. The material response has been investigated over a wide range of intensities and irradiation times. Applications include heat treatment and ablation of surfaces, cutting, drilling, and welding of a wide variety of materials, laser recording and printing, and laser surgery. Phase transitions induced by ultrashort femtosecond laser pulses enlarge our understanding of materials under extreme conditions of pressure and temperature. ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Speaker: Dr. Bijan Nemati Department of Physics, OU Date: Thursday, November 3, 1994 Time: 1:30 PM Place: Classroom Building, Room 106 Title: Recent Results from CLEO ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Not scheduled in view of Tuesday talk. ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, November 7-11, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Speaker: Dr. Mark Rakowski Institute of Theoretical Physics Dublin, Ireland Date: Thursday, November 10, 1994 Time: 1:30 PM Place: Classroom Building, Room 106 Title: State Sum Models and Simplicial Cohomology ------------------------------------------ Physics Colloquium: Speaker: Dr. Ponnada A. Narayana Department of Radiology University of Texas at Houston Date: Thursday, November 10, 1994 Time: 2:45 PM (Note Earlier Start!) Place: PS 110 Title: Magnetic Resonance Spectroscopic Imaging Refreshments served before Colloquium in Physical Sciences, Room 147, at 2:30 PM (note change of time). Also, at 11:30 AM in PS 147, a presentation by Dr. Narayana is scheduled (sponsored by The Society of Physics Students) about careers in medical physics and medical school opportunities at the University of Texas at Houston. Abstract: Since its introduction about twenty years ago into the clinical arena, magnetic resonance imaging (MRI) has rapidly become the modality of choice for visualizing central nervous system (CNS) diseases. While tissue pathology can be visualized with exquisite details, the MRI findings remain qualitative and nonspecific. In addition to generating superb anatomical images, it is also possible to map the biochemical distribution in the brain utilizing magnetic resonance. Such maps, generally known as spectroscopic images, have the potential to be disease-specific and provide quantitative information. For spectroscopic imaging (SI) to become a routine clinical tool, a number of technical obstacles have to be overcome. These include pulse sequence design for faster and robust data acquisition, automatic data processing techniques, etc. In this presentation, the basic concepts of SI will be reviewed and the technical challenges for making SI a routine clinical tool will be discussed. Finally, some recent progress made in SI and its application to both normal and diseased brain will be presented. ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Speaker: Xiaoping Cai Date: Friday, November 11, 1994 Time: 2:00 PM Place: PS 147 Title: RHEED Theory and its Application in MBE ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, November 14-18, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Cancelled ------------------------------------------ Physics Colloquium: Speaker: Dr. Paul Devlin Department of Chemistry, OSU Date: Thursday, November 17, 1994 Time: 3:30 PM Place: PS 110 Title: Nature of the Molecular Mobility of Ice at Temperatures below 150 K Refreshments served before Colloquium in Physical Sciences, Room 147, at 3:00 PM, where also the traditional student-speaker informal discussion is scheduled 2:45-3:15. Abstract: Several processes, including the growth of crystalline ice from either the vapor or amorphous phase at temperatures in the 100 - 150 K range, require rapid condensed-phase structural relaxation. Since these temperatures are presumably too low for translational molecular diffusion to occur in ice, we are examining the possibility that rotational diffusion catalyzed by orientational point defects is the source of the molecular mobility. Isotopic exchange methods of measurement of point defect activities developed in our laboratory will be examined, along with results that relate to the question of structural relaxation. ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Not scheduled ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, November 21-25, 1994 ------------------------------------------ Thanksgiving Week ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, November 28-December 2, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Speaker: Dr. Ron Kantowski Department of Physics, OU Date: Thursday, December 1, 1994 Time: 1:30 PM Place: Classroom Building, Room 106 Title: Inhomogeneities and q_0 ------------------------------------------ Physics Colloquium: Cancelled and Postponed till next Semester ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Cancelled and Postponed till next Semester ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, December 5-9, 1994 ------------------------------------------ Oklahoma High Energy Physics Seminar on Talk-Back Television: Speaker: TBA Date: Thursday, December 8, 1994 Time: 1:30 PM Place: Classroom Building, Room 106 Title: TBA ------------------------------------------ Physics Colloquium: Not Scheduled ("Dead Week" before Finals) Also cancelled in view of Dean's Office Christmas Open House Thursday, December 8, 1994, 3:00-4:00 PM ------------------------------------------ Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal): Cancelled in view of Annual Physics Department Christmas Party Friday, December 9, 1994, 2:30-4:30 PM in Room PS 147. ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, December 12-16, 1994 ------------------------------------------ Finals Week: No seminars scheduled ------------------------------------------ Noble Center for Laser Research, Annual Xmas Party, Room NRC 413, Thursday, December 16, 1994, 3:00-5:00 PM ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, December 19-23, 1994 ------------------------------------------ Special Physics Colloquium: Speaker: Dr. S. Lori Bridal Department of Physics Washington Univ. (St. Louis) Date: Thursday, December 22, 1994 Time: 2:00 PM Place: PS 110 Title: Ultrasonic Acoustic Microscopy: Broadband Ultrasonic Investigations of Inhomogeneous, Anisotropic Media Reception for Lori to follow about 3:00 PM. Lori (BS, Physics OSU) has just completed her PhD in Physics at Washington University under the direction of Professor Jim Miller. Her talk is based upon part the research undertaken for her dissertation. Lori is home in Oklahoma for a few days before leaving at the end of December to take up a Research Fellowship at the Sorbonne. ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, December 26-30, 1994 ------------------------------------------ Christmas Break: No activities scheduled ------------------------------------------ ------------------------------------------ Oklahoma State Physics Department Seminars and Colloquia, January 2-6, 1995 ------------------------------------------ No activities in view of Graduate Student Preliminary Exams: January 2, 3, 5, 6, 1995 ------------------------------------------ ------------------------------------------