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Click here for:Date: | Tuesday (usually) |
Time: | 3:00-4:00 PM |
Place: | NRC TBA |
Inquiries: | jpw519@okway.okstate.edu |
Date: | Tuesday (biweekly, fall semester only) |
Time: | 4:30 PM |
Place: | PS 147 |
Inquiries: | physpaw@mvs.ucc.okstate.edu |
or by phone at 4-5815 |
Date: | Thursday |
Time: | 1:30-3:00 PM |
Place: | Engineering North, Room 511, OSU |
& Bizzell Library, Room 104, OU | |
Inquiries: | shaown@okstate.edu or milton@nhn.ou.edu |
Date: | Thursday |
Time: | 3:30-4:30 PM |
Place: | PS 110 |
Inquiries: | flandeb@okstate.edu or perk@okstate.edu |
Date: | Friday (bi)weekly |
Time: | 2:30 PM |
Place: | PS 147 |
Inquiries: | perk@okstate.edu |
No talks scheduled
Speaker: | Dr. Carl E. Mungan |
Asst. Prof. of Physics | |
U.S. Naval Academy | |
Date: | Friday, July 18, 2003 |
Time: | 1:00 PM |
Place: | PS 101 |
Title: | Laser Cooling of Solids: Principles & Applications |
In this talk I will explain how a laser can be run "in reverse" to convert thermal energy into radiation. The history of this idea will be summarized. Experimental results will be reviewed, particularly for rare-earth doped glasses and crystals. I will discuss benchmarks toward development of a practical optical refrigerator. The concept of a radiation-balanced laser which requires no external coolant will be presented. The seminar will be geared to a general audience.
No talks scheduled
Thursday, July 31, 2003, Room PS 147
2:30 PM | Adam Wood | Temperature Dependence of Photorefraction in BGO:Mo |
2:50 PM | Daniel Bergman | Occurrence and Growth Rates of Band Pattern Formation in a Rotating Suspension of Settling Particles within a Cylinder |
3:10 PM | Carolyn Horton | Electroluminiscence in Lead/Mercury Chalcogenide-PVK Nanocomposites and Applications to Microresonators |
3:30 PM | Andrew Thornberg | Effects of Heating Rate on Thermoluminescence Efficiencies |
3:50 PM | Lesley Hess | Fracture Detection of Ceramic Material Using Terahertz Impulse Ranging |
Note: For more detail see the REU 2003 Presentations webpage.
Friday, August 1, 2003, Room PS 147
2:00 PM | Ryan Scott | Electronic Properties of the Lowest Excited Triplet State of Porphyrin |
2:20 PM | L. Suzanne Leslie | Laser Cooling and Bose-Einstein Condensation |
2:40 PM | Jerrod Stutzman | Vibrational Spectroscopy of Butyramide and its Application to Structure-Function Studies of Photoactive Yellow Protein |
3:10 PM | Eric Tong | Temperature Effects on the Surface Pressure-Area Isotherms of Tri-Octyl Phosphine Oxide Monolayers |
3:30 PM | Trenton McKinney | Characterization of Pristine and HNO3 Functionalized Single Wall Carbon Nanotubes Using Raman Spectroscopy |
Note: For more detail see the REU 2003 Presentations webpage.
No talks scheduled
No talks scheduled
First Week of Classes
Speaker: | Dr. Evgeni Fedorovich |
& Dr. Alan Shapiro | |
School of Meteorology | |
University of Oklahoma | |
Date: | Tuesday, August 19, 2003 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Analytical and Numerical Modeling of Convection along Vertical and Horizontal Heated Surfaces |
A brief overview will be presented of some recent atmospheric convection studies at the School of Meteorology, University of Oklahoma, and Oklahoma Weather Center in Norman, Oklahoma. Two particular cases of the buoyantly driven (convective) flows will be addressed in detail. The first is the case of transient natural convection along a heated vertical plate, a classical problem in fluid mechanics and heat transfer. The second is the case of the atmospheric convective boundary layer (CBL), which develops over a heated underlying surface of the earth during daytime. The phenomenological aspects of both investigated cases will be discussed and their relevance to meteorological and engineering applications will be shown.
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.
No talks scheduled
Speaker: | Brandy White |
Department of Physics | |
Oklahoma State University | |
Date: | Tuesday, September 2, 2003 |
Time: | 4:00 PM |
Place: | PS 110 |
Title: | Spectrophotometric Detection of Chemical and Biological Agents |
Speaker: | Dr. Jeffery L. White |
Department of Chemistry | |
North Carolina State University | |
Date: | Thursday, September 4, 2003 |
Time: | 3:30 PM |
Place: | PS 103 |
Title: | Experimental Evidence For the Role of Configurational Entropy in Polymer Miscibility |
We present experimental evidence for increased local entropy in a high-molecular weight polymer upon blend formation with a second, higher Tg, polymer. Direct spectroscopic observation of conformational dynamics by 2D solid-state NMR reveals an increase in the absolute configurational entropy of a one-million molecular weight polymer, polyisobutylene (PIB), when miscible blends with head-to-head polypropylene (hhPP) or polyethylene-co-butene (PEB) are formed. Increased conformational dynamics for the low-Tg PIB are not observed in phase-separated blends. Static 2H and 129Xe NMR experiments support this conclusion. These results contradict traditional thermodynamic models, based on Flory-Huggins theory, in which the entropy of mixing for two macromolecules is assumed to be zero. Such models are inherently based on non-local polymer structures, and fail to account for specific dynamics at sub-Rg length scales. Our experimental results on saturated hydrocarbon blends, in which enthalpic interactions are small due to the identical chemical composition of polyolefins, indicate that the cumulative conformational entropy gains upon mixing can reach values up to ln(3)N, where N is the number of backbone bonds. Polyolefin miscibility is poorly understood from the most fundamental perspective, and our recent results add a heretofore inaccessible range of experimental data. Recent results also indicate that the characteristic glass-transition length scale is less than the polymer radius of gyration, and the Tg timescale is on the order of several seconds.
Note: Refreshments will be served at 3:00 P.M. in room PS 117.
Host: Dr. Warren T. Ford, wtford@okstate.edu.
Speaker: | Dr. Supryia Jain |
Department of Physics and Astronomy | |
University of Oklahoma | |
Date: | Thursday, September 11, 2003 |
Time: | 1:30 PM |
Place: | Engineering North, Room 511, OSU |
& Bizzell Library, Room 104, OU | |
Title: | Search for t-tbar Resonances with D0 Data |
Thursday, September 11, 2003, Room PS 110
3:30 PM | Dr. Paul Westhaus | General Introductory Remarks |
3:50 PM | Dr. Jacques H.H. Perk | Using Models in Statistical Mechanics |
4:10 PM | Dr. Bret Flanders | Probing Mesoscopic Properties in Langmuir Films |
Note: This is the first series of informal presentations on research activities and opportunities in the department. All students are welcome! There will be ample time for questions. Refreshments will be served starting 3.00 PM and during the breaks.
Speaker: | Dr. Birgit Kaufmann |
Department of Physics, OSU | |
Date: | Friday, September 12, 2003 |
Time: | 1:30 PM |
Place: | PS 147 |
Title: | Non-Equilibrium Effects in Bose-Einstein Condensates in an External Periodical Potential |
We are investigating the quantum phase transition between the Mott insulating phase and the superfluid phase in a Bose-Einstein condensate of trapped ultracold atomic gases in an external optical lattice. Experimentally, this phase transition can be studied in great detail due to the fact that all relevant parameters can be continuously varied across the transition, as was shown by Greiner et al. in recent experiments (Nature 415, 39 (2002)). Theoretically, the system can be described by the Bose-Hubbard model. We are introducing a non-equilibrium situation by coupling the one-dimensional system to external leads so that particles will flow into the system at one end and out of the system at the other end. Numerical diagonalization techniques are used to study the properties of this system. We will show preliminary results for the case where a stationary flow is established.
Speaker: | Steven Coleman |
School of Electrical & Computer Engineering | |
Oklahoma State University | |
Date: | Tuesday, September 16, 2003 |
Time: | 4:00 PM |
Place: | PS 110 |
Title: | Progress in THz Bandwidth Interconnects |
Thursday, September 18, 2003, Room PS 110
3:30 PM | Dr. Gil Summy | Bose-Einstein Condensation |
3:50 PM | Dr. Xincheng Xie | A Few Aspects of Condensed Matter Theory |
4:10 PM | Dr. Kaladi Babu | Selected Topics in High Energy Physics Research |
Note: This is the second series of informal presentations on research activities and opportunities in the department. All students are welcome! There will be ample time for questions. Refreshments will be served starting 3.00 PM and during the breaks.
Speaker: | Dr. Arif Mamedov |
Nomadics, Inc. | |
Date: | Friday, September 19, 2003 |
Time: | 2:30 PM |
Place: | PS 103 |
Title: | Carbon Nanotube Based Composite Materials |
Speaker: | Shuhui Qin |
Department of Chemistry | |
Oklahoma State University | |
Date: | Friday, September 19, 2003 |
Time: | 3:00 PM |
Place: | PS 103 |
Title: | Grafting Polymers to Single-Wall Carbon Nanotubes |
Speaker: | Dr. Gerhart Seidl |
Department of Physics | |
Oklahoma State University | |
Date: | Thursday, September 25, 2003 |
Time: | 1:30 PM |
Place: | Engineering North, Room 511, OSU |
& Bizzell Library, Room 104, OU | |
Title: | Casimir Energy in Deconstruction |
Speaker: | Dr. Chris Sorensen |
Department of Physics | |
Kansas State University | |
Date: | Thursday, September 25, 2003 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Chemical Nanomachining of Nanoparticles for Size and Shape Control |
We have developed synthetic methods that allow creation of large quantities of substantially monodisperse nanoparticles. Materials include Au, Ag, Cu, and CdS. The method involves Digestive Ripening wherein a polydisperse colloid is digested at the boiling point of the solvent In the presnce of a surface active ligand to yield a monodisperse colloid. Different ligands allow for reversible size and shape control, Chemical Nanomachining. Spherical particles created in this way yield beautiful two and three dimensional superlattices. The mechanism for these processes is largely unknown.
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.
Fall Break Monday-Tuesday
Speaker: | Dr. K.S. Babu |
Department of Physics | |
Oklahoma State University | |
Date: | Thursday, October 2, 2003 |
Time: | 1:30 PM |
Place: | Engineering North, Room 511, OSU |
& Bizzell Library, Room 104, OU | |
Title: | Grand Unification and Neutrino Masses |
Speaker: | Dr. James M. Tour |
Department of Chemistry and | |
Center for Nanoscale Science and Technology | |
Rice University | |
Date: | Thursday, October 2, 2003 |
Time: | 3:30 PM |
Place: | PS 103 |
Title: | Constructing a Computer from Molecular Components and Functionalization of Carbon Nanotubes and their Polymer Blends |
(A) Research efforts directed toward constructing a molecular computer will be described in the context of recent developments in nanotechnology. Routes will be outlined from the synthesis of the basic building blocks such as wires and alligator clips, to the assembly of the processing functional blocks. Specific achievements include: (1) isolation of single molecules in alkane thiolate self-assembled monolayers and addressing them with an STM probe, (2) single molecule conductance measurements using a mechanically controllable break junction, (3) 30 nm bundles, approximately 1000 molecules, of precisely tailored molecular structures showing negative differential resistance with peak-to-valley responses far exceeding those for solid state devices, (4) dynamic random access memories (DRAMs) constructed from 1000 molecule units that possess 15 minute information hold times at room temperature, (5) demonstration of single-molecule switching events and (6) initial assemblies and programming of molecular CPUs in a NanoCell configuration that show room temperature electronic memory with days or electronic hold time, and the programming of molecular logic gates.
(B) Routes to functionalization and characterization of carbon nanotubes will be discussed. This will include a solvent-free process that makes the functionalized systems accessible at low cost. Blending $LT;1 wt % of these functionalized materials into commodity elastomers can increase the tensile modulus several-fold, while retaining the original elongation-to-break properties. Secondly, blending 1 wt % nanotubes into commodity plastics, followed by short (3 second) exposure to low power microwaves (60 W) can result in crosslinks at the exposed locations for localized modulus changes. Thirdly, the development of lightweight materials for EM radiation absorbing or shielding (reflection) has been achieved; the two processes varying simply by a sub-millimeter surface treatment.
Note: Refreshments will be served at 3:00 P.M. in room PS 117.
Host: Dr. Warren T. Ford, wtford@okstate.edu.
Speaker: | Dr. Jacques H.H. Perk |
Department of Physics, OSU | |
Date: | Friday, October 3, 2003 |
Time: | 1:30 PM |
Place: | PS 147 |
Title: | Square-Lattice Dimer Model, Fully-Frustrated Ising Model, and Ising Model in Field iπkT/2 |
Factorized in Terms of Two Zero-Field Ising Models |
Speaker: | Kai Wang |
Department of Physics | |
Oklahoma State University | |
Date: | Thursday, October 9, 2003 |
Time: | 1:30 PM |
Place: | Engineering North, Room 511, OSU |
& Bizzell Library, Room 104, OU | |
Title: | Solving the Problems of Supersymmetry with Discrete Gauge Symmetries |
Speaker: | Dr. Yun Wang |
Department of Physics and Astronomy | |
University of Oklahoma | |
Date: | Thursday, October 9, 2003 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Probing Fundamental Physics with Cosmological Data |
The structures in our universe have grown from tiny primordial matter fluctuations. The theory of inflation tells us that these primordial seeds were quantum fluctuations generated during a period of exponential expansion of the very early universe. The basic cosmological parameters (expansion rate of the universe, baryon density of the universe, matter density of the universe, geometry of the universe, etc) and the power spectrum of the primordial matter fluctuations together provide a fundamental picture of our universe.
I will discuss three complimentary probes of our universe: (1) the anisotropy of the cosmic microwave background radiation; (2) the large scale distribution of galaxies; (3) the brightness of cosmological standard candles (type Ia supernovae). I will show how observational data can allow the accurate measurement of important cosmological parameters, a measurement of the primordial power spectrum independent of inflationary models, and strong constraints on the nature of the unknown energy in the universe.
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.
Postponed till next week, due to special A&S meeting called by OSU president.
Speaker: | George Farca |
Department of Physics | |
Oklahoma State University | |
Date: | Tuesday, October 14, 2003 |
Time: | 4:00 PM |
Place: | PS 110 |
Title: | Whispering Gallery Modes and Dielectric Microspheres |
Speaker: | Dr. Kim Milton |
Department of Physics and Astronomy | |
University of Oklahoma | |
Date: | Thursday, October 16, 2003 |
Time: | 1:30 PM |
Place: | Engineering North, Room 511, OSU |
& Bizzell Library, Room 104, OU | |
Title: | Recent Controversies in the Casimir Effect: Temperature, Entropy, and Self Energy |
Thursday, October 16, 2003, Room PS 110
3:30 PM | Dr. James Wicksted | Spectroscopy of Rare Earth Doped Glasses and Single Wall Nanotubes |
3:50 PM | Dr. Albert Rosenberger | Microresonator Optics at OSU |
4:10 PM | Dr. Eduardo G. Yukihara | Optically Stimulated Luminescence Dosimetry |
Note: This is the last series of informal presentations on research activities and opportunities in the department. All students are welcome! There will be ample time for questions. Refreshments will be served starting 3.00 PM and during the breaks.
Speaker: | Dr. Jim Wicksted |
Department of Physics | |
Oklahoma State University | |
Date: | Friday, October 17, 2003 |
Time: | 2:30 PM | Place: | PS 103 |
Title: | Raman Scattering applied to Single-Wall Carbon Nanotubes |
Speaker: | Mr. Muhammed Gheith |
Department of Physics | |
Oklahoma State University | |
Date: | Friday, October 17, 2003 |
Time: | 3:00 PM |
Place: | PS 103 |
Title: | Gold Nanoparticles as Potential Sensors |
Speaker: | Siyka Shopova |
Department of Physics | |
Oklahoma State University | |
Date: | Tuesday, October 21, 2003 |
Time: | 4:00 PM |
Place: | PS 110 |
Title: | Whispering Gallery Modes and Microlasers |
Speaker: | Dr. Regina Kalchgruber |
Department of Physics | |
Oklahoma State University | |
Date: | Wednesday, October 22, 2003 |
Time: | 3:30 PM |
Place: | LSE 216 |
Title: | Luminescence Dating on Mars: |
Why Martian Sediments Should Use Sun Cream! |
Speaker: | Dr. Frank Paige |
Brookhaven National Laboratory | |
Date: | Thursday, October 23, 2003 |
Time: | 1:30 PM |
Place: | Engineering North, Room 511, OSU |
& Bizzell Library, Room 104, OU | |
Title: | SUSY Studies for ATLAS at LHC |
Speaker: | Dr. Ravi K. Vadapalli |
Department of Physics | |
Oklahoma State University | |
Date: | Thursday, October 23, 2003 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Quantum Fluid Dynamics Approach for Solving the |
Time-Dependent Schrödinger Equation on Parallel Computers |
This presentation discusses advantages of the quantum fluid dynamics (QFD) approach, developed from Bohm’s hydrodynamic formulation [1], whereby the time-dependent Schrödinger equation (TDSE) is transformed to observing the dynamics of a “fluid continuum.” The density and velocity of the fluid are derived from the amplitude and phase components of the wave function in polar form. The fluid is discretized into a set of “pseudoparticles” (i.e., the particles of the fluid continuum) and their dynamics are coupled through the continuity equation and the quantum potential. This approach is very attractive, since it connects the seemingly disjoint classical and quantum mechanical theories of matter through the well-known Hamilton-Jacobi (HJ) theory, and the quantum potential. Since the distribution of pseudoparticles among the available processors is naturally scalable, the QFD approach is particularly suitable for parallel and distributed computing architectures. Hence, we implemented the method for distributed computing environment using message-passing interface (MPI) and carried out several numerical experiments to investigate the accuracy of the method as well as its scalability and parallel performance [2]. In this presentation, results of our preliminary numerical experiments on model problems such as a moving free particle [3], or harmonic oscillator [4] will be presented. Advantages of the QFD formalism for visualization will be demonstrated through a one-dimensional barrier penetration [5] problem. This talk concludes with future work and discusses the prospects of this approach to simulate Quantum Chaos in the semiclassical limit.
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.
Speaker: | Dr. Nick Materer |
Department of Chemistry | |
Oklahoma State University | |
Date: | Friday, October 24, 2003 |
Time: | 2:30 PM |
Place: | PS 103 |
Title: | Adsorption of Cyanogen Halides on Silicon (100) Surface Studied by XPS and UPS |
The surface functionalization of group IV semiconductors, in particular Si(100), with organic molecules promises the opportunity to create devices that exploit the combined properties of organic materials and conventional semiconductors. The adsorption and chemical bonding of organic molecules to fine-tune the chemical and physical properties of the surface has applications in chemical sensors, biological recognition, and molecular and optical electronics. To realize these applications, a fundamental understanding of the reactivity of the Si(100) surface towards various organic compounds is required. Our investigations focus on the reactivity of the carbon nitrogen triple-bond. In particular, we employ cyanogen halides (ClCN, BrCN and ICN) as models for the CN triple bond functionality in order to observe the adsorption and decomposition in a straightforward manner. X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) are utilized to investigate the adsorption of cyanogen halides on the Si (100) surface. At 100 K, XPS results have shown that the CN triple bond remains intact for submonolayer exposures. The UPS spectra reveal two peaks that are assigned to the pi electrons in the CN triple bond, indicating that some fraction of XCN adsorbs molecularly at 100 K. The XPS and UPS measurements conducted at room temperature support complete X-CN bond cleavage at 298 K, leaving an intact adsorbed CN species. Upon annealing to higher temperatures, XPS and UPS measurements reveal that the CN bond is stable until approximately 700 K. At even higher temperatures, silicon carbides and nitrides form.
Speaker: | Dr. Ulrich Baur | Department of Physics |
State University of New York at Buffalo | |
Date: | Thursday, October 30, 2003 |
Time: | 1:30 PM |
Place: | Engineering North, Room 511, OSU |
& Bizzell Library, Room 104, OU | |
Title: | Electroweak Radiative Corrections to Weak Boson Production at Hadron Colliders |
Speaker: | Dr. Ulrich Baur | Department of Physics |
State University of New York at Buffalo | |
Date: | Thursday, October 30, 2003 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | High Energy Colliders and the Origin of Electroweak Symmetry Breaking |
The Standard Model of Particle Physics predicts the existence of a Spin 0 boson, the so-called Higgs Boson, which is responsible for generating the masses of quarks, leptons and the electroweak gauge bosons. I review the properties of the Higgs boson and discuss how well high energy colliders may determine those. In particular I discuss how well the Higgs potential can be reconstructed in future experiments.
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.
Speaker: | Dr. Wei R. Chen |
Director of Biomedical Engineering Program | |
Department of Physics and Engineering | |
University of Central Oklahoma | |
Date: | Thursday, November 6, 2003 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Laser Treatment of Cancers with Augmentation of Immunological Stimulations |
Tumor invasion and metastasis is the major cause of treatment failure for cancer patients. Tumor metastases often occur so early that by the time primary tumors are diagnosed, about 30% of patients with solid tumors have already had clinically detectable metastases, and another 30% of patients have had clinically occult micrometastases. Most current treatment modalities have a limited effect in treating metastatic tumors.
A novel approach—laser immunotherapy—was developed. It utilizes dye-assisted selective laser-tissue interaction for direct tumor destruction and an adjuvant-regulated immunological stimulation. Specifically, an 805-nm diode laser and indocyanine green were used for the selective photothermal interaction, and a novel immunoadjuvant, glycated chitosan, was used as the immunostimulant.
Our experiments using laser immunotherapy in treating metastatic mammary tumors in rats have shown promising results, including (1) eradication of treated primary tumors and regression of untreated metastases at remote sites, (2) resistance to tumor rechallenges in rats successfully treated by laser immunotherapy, (3) detection of serum antibodies from successfully treated tumor-bearing rats that strongly bind to the plasma membranes and other products of tumor cells, and (4) anti-tumor immunity induced by laser immunotherapy that can be adoptively transferred using immune spleen cells.
These results strongly indicate a systemic, long-term, anti-tumor immunity induced by the laser immunotherapy. If proven successful in clinical applications, this technique could become an effective tool in the fight against deep, late-stage, and metastatic tumors through a local, minimally invasive treatment.
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.
Speaker: | Dr. Hongbin Lu |
School of Mechanical and Aerospace Engineering | |
Oklahoma State University | |
Date: | Friday, November 7, 2003 |
Time: | 2:30 PM |
Place: | PS 103 |
Title: | Measurements of Creep Functions in Both Time and Frequency Domains Using Nanoindentation |
Methods will be presented for the measurements of the local surface creep functions in both time and frequency domains for time-dependent materials such as polymers using nanoindentation. Continuum mechanics solutions of the viscoelastic indentation problems are used to derive formulas to determine the creep compliance in the time domain, and complex creep function in the frequency domain. These formulas are validated through experiments on two bulk polymers, Polymethyl Methacrylate (PMMA) and Polycarbonate (PC). Both Berkovich and spherical nanoindenters were used to indent into the material in nanoindentation tests. Two loading histories were used: (1) a ramp loading history, in which the indentation load and displacement were recorded; and (2) a step loading history, in which the indentation displacement was recorded as a function of time. Analysis of the linear viscoelastic material response was performed to determine the load-displacement curves under different loading histories. The limit of linear viscoelastic behavior for each of the two materials was determined through the observation of the indent impression recovery after complete unloading; it is postulated that linearity is achieved if indentation impression is fully recovered after unloading. Results from nanoindentation tests generally agree well with data from conventional tension and shear tests. It has thus validated the techniques of measuring linear creep compliance in the glassy state using nanoindentation with the Berkovich and spherical indenter tips. The methods for the characterization of linear viscoelastic materials using nanoindentation are expected to be applicable to very small amounts of materials, such as thin films, and heterogeneous materials such as composites and bones.
Speaker: | Dr. Paul Clem |
Principle Member of Technical Staff | |
Sandia National Laboratories | |
Date: | Tuesday, November 11, 2003 |
Time: | 3:30 PM |
Place: | EN 108 |
Title: | Sol-Gel Deposition of Oxide Thin Films: Ferroelectric MEMS and Superconducting Tapes |
Sol-gel chemistry enables integration of dense oxide films on semiconductor and metal substrates at greatly reduced temperatures in comparison to traditional ceramic powder processing. In particular, ‘active’ ceramics with exceptional dielectric, piezoelectric, nonvolatile memory, and superconducting properties may be deposited with either random crystallographic or single crystal-like orientations. Ferroelectric thin films enable a variety of novel electronic devices, especially when integrated with bulk or surface micromachined silicon substrates. In particular, the large piezoelectric coefficients of materials such as Pb(Zr,Ti)O3 [PZT] are ideal for micromachined silicon actuators and force sensors. Bulk micromachined MEMS devices produced by integration of PZT thin films will be presented, as well as integration and processing strategies for ferroelectric thin films on a variety of other substrates. For high current density applications, superconducting wires based on solution-derived, biaxially textured YBa2Cu3O7−δ (YBCO) films atop flexible substrates have been studied by a several techniques, including 18O SIMS, high resolution transmission electron microscopy (HRTEM), HRTEM spectral chemical analysis, and in-situ stress analysis. In this composite, YBCO and SrTiO3 films are grown epitaxially on biaxially-oriented Ni (200) or NiW (200) tape via solution deposition. Current transport in the tape is controlled by YBCO epitaxial film structural quality, chemical composition, and film thickness. Methods of controlling film epitaxial growth and means of optimizing superconducting properties will be presented.
Sandia is a multiprogram laboratory operated by Sandia Corp., a Lockheed Martin Company, for the USDOE under contract DE-AC04-94A185000.
Refreshments will be served at 3:15 p.m. Doors will close at 3:30 p.m.
Speaker: | Dr. Y. Nomura |
Department of Physics | |
University of California at Berkeley | |
Date: | Thursday, November 13, 2003 |
Time: | 1:30 PM |
Place: | Engineering North, Room 511, OSU |
& Bizzell Library, Room 104, OU | |
Title: | Grand Unification at Warped Space |
Speaker: | Dr. Michael Ma |
Department of Physics | |
University of Cincinnati | |
Date: | Thursday, November 13, 2003 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Oxides, Oxides Everywhere, Where is the Physics? |
New transition metal oxides are regularly being produced in the laboratory. Other than high Tc superconductivity and CMR, what new physics can we learn from these systems? In this talk, I will concentrate on the insulating oxides. In such oxides, the ordering and fluctuations of orbital degrees of freedom often clash with those of the spin degrees of freedom, leading to interesting effects such as dynamically generated reduced dimensionality, anisotropic magnetic and/or orbital ordering, orbital driven spin-Peierls transition, and new neutron active collective modes.
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.
Speaker: | Dr. Michael Ma |
Department of Physics | |
University of Cincinnati | |
Date: | Friday, November 14, 2003 |
Time: | 1:30 PM |
Place: | PS 147 |
Title: | Unconventional Ordering in the Compass Model for Orbitals |
Cancelled
Thursday, November 20, 2003, Room PS 110
3:30 PM | Dr. H. James Harmon |
Title: | No, You Can't Blow Things Up—The Problem with High Explosives |
4:00 PM | Dr. Timothy Wilson |
Title: | Electronic Structure of the Excited States of Free-Base Porphyrin |
and the Metallo-Porphyrins (ZnP and FeP) |
Abstract (of Dr. Wilson's talk): The low-lying excited states of the free-base porphyrin (FBP) and the metallo-porphyrins (ZnP and FeP) have been calculated using the single-excitation configuration interaction (CIS) and time-dependent density functional theory (TDDFT) methods. Both are first principles methods for calculating the excitation energies and oscillator strengths of the optical excitations of many-electron systems. The results are used to describe the two-photon absorption process in the FBP and ZnP. The striking differences in the absorption spectra of FeP, and those of ZnP and the FBP is discussed.
Note: This is the final series of informal presentations on research activities and opportunities in the department. All students are welcome! There will be ample time for questions. Refreshments will be served starting 3.00 PM and during the breaks.
Speaker: | Dr. Yumin (Fisher) Zhang |
School of Electrical and Computer Engineering | |
Oklahoma State University | |
Date: | Friday, November 21, 2003 |
Time: | 2:30 PM |
Place: | PS 103 |
Title: | Grating Structure and Its Applications |
Grating structures with 100 nanometer feature size can be reliably fabricated by electron bean lithography. Besides the conventional application in optics, these structures can also be used as reflector, coupler and sensor. This talk will cover the fabrication procedures and some of its applications.
Thanksgiving
Prefinals Week
Speaker: | Dr. Heidi Fearn |
Department of Physics | |
California State University at Fullerton | |
Date: | Thursday, December 4, 2003 |
Time: | 3:30 PM |
Place: | PS 110 |
Title: | Quantum Erasers and the Principle of Complementarity |
The object of this colloquium is to examine the principle of complementarity and to show that it is NOT the Heisenberg uncertainty principle which forces complementarity but wave-particle duality is deeper, and the true cause of the effect is buried in the wave function.
As an example we will show Einstein's single slit experiment and Feynman's light scattering scheme, which seem to suggest you need the uncertainty principle to explain complementarity. Then we consider an atom interference experiment which clearly does not depend on the uncertainty relation dx dp>h/2 .
I will show both theory and experiment and hope to convince the audience that the wave function itself is all we need to explain complementarity, although sometimes it is more convenient to use the uncertainty principle.
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.
Cancelled
Finals Week
No talks scheduled
No talks scheduled
No talks scheduled
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This page was prepared by Helen Au-Yang and Jacques H.H. Perk.
jhhp@jperk.phy.okstate.edu