Seminars and Colloquia, July through December, 2000

• This Week's schedule.
• Earlier Semesters.
• Typical Week's schedule.
• July 3-7, 2000's schedule.
• July 10-14, 2000's schedule.
• July 17-21, 2000's schedule.
• July 24-28, 2000's schedule.
• July 31-August 4, 2000's schedule.
• August 7-11, 2000's schedule.
• August 14-18, 2000's schedule.
• August 21-25, 2000's schedule.
• August 28-September 1, 2000's schedule.
• September 4-8, 2000's schedule.
• September 11-15, 2000's schedule.
• September 18-22, 2000's schedule.
• September 25-29, 2000's schedule.
• October 2-6, 2000's schedule.
• October 9-13, 2000's schedule.
• October 16-20, 2000's schedule.
• October 23-27, 2000's schedule.
• October 30-November 3, 2000's schedule.
• November 6-10, 2000's schedule.
• November 13-17, 2000's schedule.
• November 20-24, 2000's schedule.
• November 27-December 1, 2000's schedule.
• December 4-8, 2000's schedule.
• December 11-15, 2000's schedule.
• December 18-22, 2000's schedule.
• December 25-29, 2000's schedule.

Seminars and Colloquia, Typical Week:

Center for Laser and Photonics Research Seminar:

Center for Sensors & Sensor Technologies Seminar:

Physics Undergraduate Journal Club:

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Physics Colloquium:

Journal Club on Statistical Mechanics and Condensed Matter Physics (Informal):

Oklahoma State Physics Department

Seminars and Colloquia, July 3-7, 2000

No talks scheduled

Oklahoma State Physics Department

Seminars and Colloquia, July 10-14, 2000

Research Experience for Undergraduates Colloquium:

Oklahoma State Physics Department

Seminars and Colloquia, July 17-21, 2000

No talks scheduled

Oklahoma State Physics Department

Seminars and Colloquia, July 24-28, 2000

Research Experience for Undergraduates Presentations:

Wednesday, July 26, 2000, Room PS 147

Research Experience for Undergraduates Presentations:

Thursday, July 27, 2000, Room PS 147

Oklahoma State Physics Department

Seminars and Colloquia, July 31-August 4, 2000

No talks scheduled

Oklahoma State Physics Department

Seminars and Colloquia, August 7-11, 2000

Center for Laser and Photonics Research Seminar:

Note:

3:00 -- Refreshments
3:15 -- Presentation
Question & Answer Period following.

Oklahoma State Physics Department

Seminars and Colloquia, August 14-18, 2000

No talks scheduled

Oklahoma State Physics Department

Seminars and Colloquia, August 21-25, 2000

No talks scheduled

Oklahoma State Physics Department

Seminars and Colloquia, August 28-September 1, 2000

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Oklahoma State Physics Department

Seminars and Colloquia, September 4-8, 2000

Frontiers in Physics (Physics Undergraduate Journal Club):

Dr. Bruce Ackerson will lead a discussion on "One Hundred Years of Quantum Physics" by Daniel Kleppner and Roman Jackiw, which appeared in Science Vol. 289 of 11 August 2000, pp. 893-898.

Everyone is welcome.

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Joint Chemistry-Physics Colloquium:

Abstract:

The seminar will be a presentation of the new electronic resources available through the OSU Library's redesigned Web site. The focus of the talk will be how to use the Library's new online catalog, and other science-related data bases to find books, articles, and technical reports related to the field of chemistry. A demonstration of computer-based literature searches will be presented.

Note room change.

Note: Coffee $AMP; Donuts will be served at 3:00 PM in Room 117 PS I.

Oklahoma State Physics Department

Seminars and Colloquia, September 11-15, 2000

Center for Laser and Photonics Research Seminar:

Abstract:

Transition metal oxides (TMOs) display an enormous range of phenomena that depend strongly on structure, doping, and temperature. Examples include the metal-insulator transition, high temperature superconductivity, and negative magnetoresistance. In the case of hole-doped TMOs, the electrons are mobile and conductivity measurements can provide information about the low-energy excitations. By combining terahertz spectroscopy with femtosecond optical excitation, the ultrafast picosecond conductivity can be measured, providing an additional degree of freedom for unraveling the dynamics of such complex systems. Ultrafast picosecond measurements will be discussed for two types of hole-doped TMOs: La_0.7M_0.3MnO₃ (M = Ca, Sr), which displays "colossal" magnetoresistance, and the high temperature superconductor Tl₂Ba₂CaCu₂O₈ (T1-2212).

Note:

Refreshments will be provided.

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Oklahoma State Physics Department

Seminars and Colloquia, September 18-22, 2000

Frontiers in Physics (Physics Undergraduate Journal Club):

Everyone is welcome.

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Physics Colloquium:

Abstract:

One of the great mysteries in physics is why the gravitational force is so much weaker than the other forces in nature. There have been many proposed explanations for this over the years. Most of these involve dramatic changes in our current percetiption of particle physics. I discuss in detail the idea that large extra dimensions explain the weakness of gravity, and present a path by which we can test if the idea is correct.

Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3.00 PM. All students are welcome. Refreshments will be served.

Laser and Photonics Research Seminar:

Abstract:

The transmittable bandwidth over optical fiber doubles about every nine to twelve months. Already transmission of tens of terabits per second over a single optical fiber is possible. Matching data transferring topologies and improved system reliability are currently in need. These can be achieved through multiprotocol label switching (MPLS), which utilizes a simple label switching mechanism and provides quality of service (QoS) features through traffic engineering. MPLS provides scalability and flexibility to the network architecture. It also enables high quality end-to-end service features that are necessary in applications such as virtual private networks (VPN). The signaling algorithms currently being used for traffic engineering are the constraint-based routing label distribution protocol (CR-LDP) and the resource reservation protocol (RSVP). Additionally, extensions to RSVP (E-RSVP) are currently being negotiated by the IETF. In this presentation, the signaling procedures, advantages and disadvantages of CR-LDP, RSVP and E-RSVP are analyzed for MPLS networking applications.

Note:

Refreshments will be provided.

Oklahoma State Physics Department

Seminars and Colloquia, September 25-29, 2000

Physics Colloquium:

Abstract:

The formation of laser-induced holographic gratings in glasses has been an active field of research for over 20 years. This is motivated by their potential applications, such as in wavelength division filters and fiber-optic Bragg sensors. In this talk, I will give a brief history on Bragg gratings in photorefractive materials, and discuss the potential applications and theories that underlie laser-induced gratings in Europium doped alkali silicate glass materials.

Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3.00 PM. All students are welcome. Refreshments will be served.

Journal Club on Statistical Mechanics and Condensed Matter Physics:

Oklahoma State Physics Department

Seminars and Colloquia, October 2-6, 2000

Fall Break

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Oklahoma State Physics Department

Seminars and Colloquia, October 9-13, 2000

Frontiers in Physics (Physics Undergraduate Journal Club):

Dr. Al Rosenberger will discuss "Quantum Teleportation" by Anton Zeilinger, which appeared in Scientific American, April 2000, pp. 50-59

The discussion will be held Tuesday, October 10, 2000 at 4:30 pm in Room 147 PS II

Abstract:

The science-fiction dream of "beaming" objects from place to place is now a reality---at least for particles of light

Note: Copies of the articles may be picked up (free of charge) in PS 145, the General Physics office, anytime prior to the discussion.

Everyone is welcome.

Physics Colloquium:

Abstract:

Neutrino flavor oscillations can occur if neutrinos violate the principle of equivalence or Lorentz invariance. It will be shown that data from solar and atmospheric neutrino experiments provide a very stringent constraint on such a violation.

Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3.00 PM. All students are welcome. Refreshments will be served.

Oklahoma State Physics Department

Seminars and Colloquia, October 16-20, 2000

Center for Sensors and Sensor Technologies Seminar:

Abstract:

The goal of this project is to extend the temperature range of an existing (Halliburton) quartz microbalance pressure system to 200°C, while reducing the size and power consumption of the sensor electronics. The design will be based on using a Peregrine SOS and as appropriate a Honeywell HTMOS^TM 2000 series PGA device. The proposed system foregoes the more traditional analog mixer for an "all" digital solution for robustness of implementation and CV²f power advantages. Oscillator design through the pressure output count will be covered in addition to the lowpower high temperature advantages offered by fully depleted SOI circuits.

At high temperature fully depleted SOI transistors have much lower leakage currents than traditional bulk MOSFETs. In addition, fully depleted devices have a 2 to 3 times lower variation in the threshold voltage (0.8mV/C) with temperature than bulk devices. Finally, electrical current cannot flow to the substrate. It can only flow in the branches of the circuits (where it is supposed to flow). While degradation in mobility remains the same as for bulk. As a result, SOI circuits can be operated at temperatures up to 400°C. As a result of using thin film fully depleted SOS, it is projected that digital gates can be fabricated, which operate in excess of 1 GHz on 1.2 to 1.6 V power supplies with only minor increases in power dissipation. The increase in power dissipation is primarily due to the increase in subthreshold currents (reducing V_T).

Note:

Refreshments will be served @ 3:00 pm in Physical Sciences II, Room 147.

Society of Physics Students Seminar:

Abstract:

Using a variety of lasers and magnetic fields, it is possible to cool a gas of atoms to a temperature near 100 nano-Kelvin above absolute zero. At these temperatures the wave-like characteristics of atoms are enhanced, allowing new studies of the exotic, quantum-mechanical nature of matter. I will discuss these cooling mechanisms and their applications to atomic clocks, atom interferometry, and Bose-Einstein condensation.

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Physics Colloquium:

Abstract:

Methods of laser cooling and atom trapping have led to advances in atom optics, atom interferometry, atomic clocks, atomic and molecular spectroscopy, and Bose-Einstein Condensation (BEC). Recent studies revealed the necessity for new types of atom traps and new trap geometries for progress in atomic clock designs and BEC experiments. I will discuss the background of these developments and the creation of new atom traps at the University of Oklahoma based on Laguerre-Gaussian laser beams of previously unobtainable mode purity.

Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3.00 PM. All students are welcome. Refreshments will be served.

Oklahoma State Physics Department

Seminars and Colloquia, October 23-27, 2000

Frontiers in Physics (Physics Undergraduate Journal Club):

Everyone is welcome.

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Cancelled

Joint Physics and Chemistry Colloquium:

Abstract:

Nanoelectronics is an exciting area of condensed matter research which may well play an important role for the search of new generations of functional devices. At truly nano-meter scale, electrical conduction can however be dominated by quantum phenomena for which some of our classical understanding of device physics need to be extended. In this talk I will discuss theoretical issues concerning the prediction of quantum transport properties of conductors at atomic and molecular scale, where such effects as the device-electrode interaction, the atomic/molecular orbitals, and the device coupling to environment, must be treated from first principles. Specific examples of charge transfer doping induced molecular current switching and anomalous quantum contribution to capacitance will be reported.

Note: The traditional student-speaker chat will begin in Physical Sciences Room 117 (Chemistry Conference Room) at 3.00 PM. All students are welcome! Coffee & Donuts will be served.

Journal Club on Statistical Mechanics and Condensed Matter Physics:

Oklahoma State Physics Department

Seminars and Colloquia, October 30-November 3, 2000

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Physics Colloquium:

Postponed

Oklahoma State Physics Department

Seminars and Colloquia, November 6-10, 2000

Frontiers in Physics (Physics Undergraduate Journal Club):

Everyone is welcome.

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Physics Colloquium:

Abstract:

Turbulent thermal convection is an intriguing problem in nonlinear physics and has attracted much attention in recent years. Despite its special way of generating turbulence at large length scales and its relatively low Reynolds number (Re), turbulent convection shares many common features that are usually associated with high-Re turbulent flows. These features include coherent structures, intermittent fluctuations and anomalous scaling. In this talk I will briefly review the recent development in the study of turbulent thermal convection and report our recent velocity and temperature measurements in the convection cells with smooth and rough conducting surfaces. Using laser Doppler velocimetry, we measured the velocity profiles in the smooth cell with different aspect ratios. Despite the large velocity fluctuations in the turbulent bulk region, the mean flow field maintains a large-scale structure, which rotates and oscillates in a coherent manner. The experiment provides an interesting example to show how otherwise random unstable modes in a closed system are organized in both space and time to generate a large-scale coherent structure in a turbulent environment. The novel convection experiment carried out in the rough cell shows that the heat transport in the rough cell is increased by more than 76% when compared with the smooth cell. Flow visualization and near-wall temperature measurements reveal new dynamics for the emission of thermal plumes. It is found that the interaction between the large-scale circulation and the rough surface creates a secondary flow (eddies) in the groove region. This secondary flow together with the large-scale circulation enhances the detachment of the thermal boundary layer from the tip of the rough elements. The extra thermal plumes are responsible for the enhanced heat transport in the rough cell. The discovery of the enhanced heat transport has important applications in engineering for more efficient heat transfer.

Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3.00 PM. All students are welcome.

Journal Club on Statistical Mechanics and Condensed Matter Physics:

Oklahoma State Physics Department

Seminars and Colloquia, November 13-17, 2000

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Physics Colloquium:

Abstract:

A variety of recent experiments indicate that neutrinos have no definite identity -- neutrinos of one "flavor" seem to oscillate into another flavor. Such oscillations would require small neutrino masses, which can arise only if the current paradigm of elementary particle physics is modified. I will argue that the most natural extension will also involve unification of the seemingly different forces of Nature. A promising approach towards addressing the pattern of neutrino masses and mixing angles within such a framework will be presented. The discovery of neutrino mass has generated a lot of excitement, several new experiments are forthcoming worldwide which will probe neutrino oscillation phenomenon in great detail. I will suggest ways in which theories of neutrino masses can be confronted with these experiments.

Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3.00 PM. All students are welcome.

Journal Club on Statistical Mechanics and Condensed Matter Physics:

Oklahoma State Physics Department

Seminars and Colloquia, November 20-24, 2000

Frontiers in Physics (Physics Undergraduate Journal Club):

Dr. Peter Shull will lead a discussion on "The Secrets of Stardust" by J. Mayo Greenberg, which appeared in Scientific American of December 2000, pp. 70-75.

Everyone is welcome.

Thanksgiving

Oklahoma State Physics Department

Seminars and Colloquia, November 27-December 1, 2000

Oklahoma High Energy Physics Seminar on Talk-Back Television:

Physics Colloquium:

Abstract:

Liquid helium I, II and cryogenic helium gas are used to generate and study highly turbulent flows under controlled laboratory conditions. These three working fluids have remarkable versatility, allowing very large dynamic ranges and upper limits for the control parameters (the Reynolds (Re) and Rayleigh (Ra) numbers) in modest academic-sized facilities. In particular, cryogenic helium gas has been used to study developed turbulent thermal convection over eleven decades of Ra in a single laboratory experiment: 10⁶ < Ra < 10¹⁷. The scaling of the effective thermal conductivity at high Ra is important to our understanding of atmospheric and stellar convection and will be discussed, as well as new results on an order-disorder transition in organized large-scale circulations. In addition to classical flows, homogeneous and isotropic turbulence is generated in helium II, a quantum fluid, and its decay probed by the attenuation of second sound. Comparisons are made with standard predictions for classical fluids.

Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3.00 PM. All students are welcome.

Oklahoma State Physics Department

Seminars and Colloquia, December 4-8, 2000

Prefinals Week

Southwest Mechanics Lecture Series:

Abstract:

Manufacturing processes that can create extremely small machines have been developed in recent years. Microelectromechanical systems (MEMS) refers to devices that have characteristic lengths of less than 1 mm but more than 1 micron, that combine electrical and mechanical components and that are fabricated using integrated circuit batch-processing techniques. Electrostatic, magnetic, pneumatic and thermal actuators, motors, valves, gears and tweezers of less than 100-micron size have been fabricated. These have been used as sensors for pressure, temperature, mass flow, velocity and sound, as actuators for linear and angular motions, and as simple components for complex systems such as micro-heat-engines and micro-heat-pumps. The technology is progressing at a rate that far exceeds that of our understanding of the unconventional physics involved in the operation as well as the manufacturing of those minute devices. This talk focuses on flow physics. Modeling gas and liquid flows through MEMS may necessitate including slip, rarefaction, compressibility, intermolecular forces and other unconventional effects. In this presentation, I shall provide a methodical approach to flow modeling for a broad variety of microdevices.

Note: Refreshments at 2:15. Further Information: (405) 744-5900 and http://www.mae.okstate.edu/.

Physics Colloquium:

Abstract:

Photoreceptors are light-activated sensory proteins involved in biological signal transduction, such as animal vision. We investigate the activation mechanism of photoactive yellow protein (PYP), a prototype photoreceptor for the PAS domain superfamily of receptor and regulatory proteins from all three kingdoms of life. Time-resolved Fourier transform infrared difference spectroscopy utilized in our study provides excellent time-resolution and structural sensitivity. We will present structural, kinetic and energetic evidence on the decisive role of light-driven intramolecular proton transfer and creation of a buried charge in activation of PYP photoreceptor. This new and basic mechanism may be employed in activation of a wide range of receptor proteins. It is intriguing that nature does not ignore simplicity in the complex world of proteins.

Note: The traditional student-speaker chat will begin in Physical Sciences Room 147 at 3.00 PM. All students are welcome. Refreshments will be served.

OSU Mathematics Seminars and Colloquia:

Note: There will be a reception in the department lounge (MS 423) at 3:30 PM. Contact persons: Dave Witte or Jiahong Wu (405-744-5688).

Oklahoma State Physics Department

Seminars and Colloquia, December 11-15, 2000

Finals Week

Oklahoma State Physics Department

Seminars and Colloquia, December 18-22, 2000

Oklahoma State Physics Department

Seminars and Colloquia, December 25-29, 2000

Last Updated: .

This page was prepared by Helen Au-Yang and Jacques H.H. Perk.
jhhp@jperk.phy.okstate.edu