Skip to Main Content

2013 Seminars

  • New Insights on Nuclear Structure at Short Distances

    Nov. 22, 2013, 1:30pm-2:30pm, OE 134

    Dr. Misak Sargsian, Professor at the physics department of FIU.

    Abstract:

    The Quantum Mechanics introduced completely new relationship between humans and the nature, one of them is the existence of principally unobservable quantitates. I will discuss the nature of these quantities, their importance and how one can think of measuring them. The particular example of such an unobservable is the distribution of nuclear matter in the space. New results on this distribution at short distances will be presented and their implication for various phenomena ranging from weak interaction to nuclear astrophysics will be discussed. Finally I will try to convince you that the observed results have a universal nature and should be observed also in Cold Atoms allowing to reproduce "neutron-star" conditions in cold atomic gases.

    Biography:

    Dr. Misak Sargsian is a full professor at the physics department of FIU. He earned his Ph.D. in Theoretical Nuclear Physics from Yerevan Physics Institute, Armenia in 1993. He joined FIU in 1999. He was an Alexander von Humboldt fellow from 1997-1998. He was elected APS fellow in 2010.

  • SIngle Molecule Spectroscopy of Amino Acids and Peptides by Recognition Tunneling

    Nov. 14, 2013, 1:30pm-2:40pm, AHC4 101

    Dr. Start Lindsay, Regent professor, Director, Center for Single Molecule Biophysics, Biodesign Institute, Arizona State University

    Abstract

    Single molecule protein sequencing is a critical enabling technology in the quest for disease-related biomarkers. Accurately identifying individual amino acid molecules is a significant step towards this goal. Recognition Tunneling (RT) can be used to identify naturally occurring amino acids, including enantiomers, modified amino acids, isobaric isomers and short peptides. The RT electronic "fingerprints" of amino acid molecules can be characterized, and subsequently automatically identified, with a machine-learning algorithm.

    Biography

    Stuart Linday, Ph.D., Specializes in biophysics at the molecular level and scanning probe microscopy. Much of his work is aimed at speedier diagnosis and an understanding of the molecular basis of disease. He holds 29 US patents and is a technology advisor for the Atomic Force Microscope Division of Agilent Technologies. Agilent has acquired Molecular Imaging Corporation, which he co-founded in 1993. Dr. Lindsay is the author of the first comprehensive text for nanoscience, "Introduction to Nanoscience" (OUP, 2009). He is a fellow of the American Association for the Advancement of Science and the American Physical Society.

  • The Triumphant Standard Model: Observation of the Rare Decay of B Mesons into Muon Pairs

    Nov. 8, 2013, 1:30pm-2:30pm, OE 134

    Marc Baarmand, Professor of Physics, Florida Tech

    Abstract:

    The Standard Model of particle physics, developed over the last 5 decades, is considered a crowning achievement of 20th century science. It remains undefeated after many stringent tests, the last of which is its prediction for the rare decay of B mesons into muon pairs. Yet, the Standard Model is believed to be incomplete as it provides no answer to some of the most intriguing questions, for example the origin of dark matter and the dominance of matter over antimatter. In this talk, I will review what a standard model entails, briefly discuss the Standard Model of particle physics, and describe the recent measurement of the rare B decays by the CMS experiment at CERN. I close by mentioning possible extensions of the Standard Model.

    Biography

    Marc Baarmand PhD in Particle Physics - University of Wisconsin - Madison, 1987

    Professor of Physics, Florida Tech PD/PI for CMS project at Florida Tech Over 400 journal publications; major discoveries: Discovery of W and Z bosons - UA1 collaboration, 1983 Discovery of top quark - D0 Collaboration, 1995 Discovery of Higgs boson - CMS Collaboration, 2012

  • The 3-D Structures and Morphologies of Disk Galaxies in SDSS

    Nov. 1, 2013, 1:30pm-2:30pm, OE 134

    Dr. Stefan J. Kautsch, Assistant professor of physics and astronomy Nova Southeastern University

    Abstract

    I present a complete catalog of edge-on disk galaxies and their 3-D structures. The catalog contains approximately 6000 objects which are carefully selected from the Sloan Digital Sky Survey and are used to analyze their structural components, including their morphologies, and multi-dimensional photometric profiles. This catalog provides a fundament for a variety of future research, including studies on dust distribution, thick disks, and halo properties.

    Biography

    Dr. Kautsch is an assistant professor of physics and astronomy at NSU in Ft. Lauderdale since 2011. Undergrad studies of physics and astronomy at U. Innsbruck (AT), Master's from U. Vienna (AT). PhD from U. Basel (CH) in 2006, supervisors were Eva Grebel (now at U Heidelberg/DE) and Jay Gallagher from U Wisconsin Madison. Then postdoc at UF Department of Astronomy with Anthony Gonzalez. Then visiting professor at Christopher Newport U in Virginia. Research interest: Galaxy Morphologies and Dark Matter, and now also astro-engineering

  • Status of the Higgs Boson Search at the LHC

    Oct. 25, 2013, 1:30pm-2:30pm, OE 134

    Dr. Jose Benitez, Member of the CMS collaboration, Former CERN Research Fellow

    Abstract:

    Following the discovery of a new Higgs-like particle on July 4th of 2012, the 2013 Nobel Prize in Physics has been awarded to the physicists Francois Englert and Peter Higgs for their theoretical prediction of the Higgs mechanism. This mechanism describes the process by which fundamental particles attain their mass and predicts the existence of a scalar particle: the Higgs boson. After reviewing the results in the bosonic channels, where the new particle was discovered, I will show the current results in the fermionic channels, where a Higgs boson signal is expected but has not yet been observed. I will describe in detail the analysis of the most sensitive fermionic channel: Higgs --> tau+tau- .

    Biography:

    Dr. Benitez is an FIU Physics alumni (B.S. degree 2004). He obtained his Ph.D. at Stanford University (2011), working in the BaBar experiment at the SLAC linear accelerator center. During 2011 to 2013 he worked as a CERN Research Fellow on the search for Higgs boson decays to tau leptons in the CMS experiment.

  • Photochemically- and Force-Initiated Brush Polymer Microarrays and Their Applications

    Oct. 18, 2013, 1:30pm-2:30pm, OE 134

    Dr. Adam B. Braunschweig, Department of Chemistry, University of Miami

    Abstract:

    We have used polymer pen lithography (PPL) and beam pen lithography (BPL), two recently developed tip-based printing methods, to create microarrays of grafted-from brush polymers. Using the unique ability of the elastomeric tips to apply a force, the first method to covalently pattern graphene by a Diels-Alder oligomerization was shown.[1] These force accelerated cycloadditions are a feasible route to locally alter the chemical and electronic composition of graphene defect and edge sites under ambient temperature and atmosphere over large (>1 cm2) areas. Alternatively BPL arrays were used to pattern acrylate and methacrylate monomers onto thiol-terminated glass slides. Subsequent exposure to UV light produced brush polymers whose length is controlled precisely by irradiation time, resulting in a 3D lithography method with sub-micrometer control over feature position, feature diameter, and feature height. Thus, PPL and BPL are powerful tools for studying photochemical and force-induced brush polymerizations, and the application of the resulting materials to sensing and electronics will be discussed. [1] Bian, S.; Scott, A.M.; Cao, Y.; Liang, Y.; Osuna, S.; Houk, K.N.; Braunschweig, A.B. J. Am. Chem. Soc. 2013 , 9240-9243.

    Biography:

    Born and raised in south Miami, went to undergrad at Cornell, where Dr. Braunschweig worked with Prof. D. Y. Sogah on group transfer polymerization. PhD with Prof. J. Fraser Stoddart at UCLA, working on molecular machines and supramolecular chemistry. Postdoc with Prof. Chad Mirkin at Northwestern University on tip-based lithography. Started independent career in the Department of Chemistry and Molecular Design Institute at NYU, but moved to UM after three years. Major independent awards: Air Force Office of Scientific Research Young Investigator Award, ACS Polymeric Materials: Science and Engineering (PMSE) Young Investigator 2014.

  • Approximate Cloaking of Acoustic and Electromagnetic Waves

    Oct. 11, 2013, 1:30pm-2:30 pm, OE 134

    Dr. Hongyu Liu, Assistant Professor, Department of Mathematics University of North Carolina, Charlotte

    Abstract

    In this talk, I will describe the recent theoretical and computational progress on our work on regularized transformation-optics cloaking. Ideal cloak makes use of singular metamaterials, posing much challenge for practical realization. Regularization is incorporated into the construction in order to avoid the singular structures.

    Biography:

    Dr. Hongyu Liu is an Assistant Professor of Mathematics at the University of North Carolina, Charlotte. He obtained his PhD in Mathematics from the Chinese University of Hong Kong in 2007 and held research positions at the University of California, Irvine (2010-2011) and University of Washington, Seattle (2007-2010). His research focuses on inverse problems, partial differential equations, metamaterials and cloaking, and numerical analysis.

  • Anisotropic Magnetothermopower in Ferromagnetic Thin Films

    Oct. 4, 2013, 1:30pm-2:30pm, OE 134

    Dr. Casey Miller, Associate Professor of Physics at the University of South Florida in Tampa

    Abstract

    Magnetothermal phenomena have become of interest in pursuit of phenomena such as the Spin Seebeck Effect [1, 2]. However, there has been credible evidence that thermal gradients along the surface normal have led to spurious results originating from the Anomalous Nernst Effect [3]. Based on such observations, it has been suggested that eliminating these unintentional thermal gradients may not be possible without completely [3] or virtually eliminating the substrate [4, 5]. In this talk, I will report that edge mounting the substrate to the thermal baths and placing the electrical contacts away from the ferromagnet effectively reduces these unwanted thermal gradients and enables the clear observation of the Anisotropic Magnetothermopower in several film/substrate combinations, with no measurable contribution from Anomalous Nernst Effect. Applying this work to samples with ferromagnets coupled to single crystal substrates may thus enable pure Spin Seebeck Effect measurements in the in-plane geometry.

    [1] K. Uchida, S. Takahashi, K. Harii, J. Ieda, W. Koshibae, K. Ando, S. Maekawa, and E. Saitoh. Observation of spin seebeck effect. Nature, 455:778–781, Aug 2008.

    [2] Jiang Xiao, Gerrit E. W. Bauer, Ken-chi Uchida, Eiji Saitoh, and Sadamichi Maekawa. Theory of magnon-driven spin seebeck effect. Phys. Rev. B, 81:214418, Jun 2010.

    [3] S. Y. Huang, W. G.Wang, S. F. Lee, J. Kwo, and C. L. Chien. Intrinsic spin-dependent thermal transport. Phys. Rev. Lett., 107:216604, Nov 2011.

    [4] A. D. Avery, M. R. Pufall, and B. L. Zink. Determining the planar nernst effect from magnetic field-dependent thermopower and resistance in nickel and permalloy thin films. Phys. Rev. B, 86:184408, Nov 2012.

    [5] A. D. Avery, M. R. Pufall, and B. L. Zink. Observation of the planar nernst effect in permalloy and nickel thin films with in-plane thermal gradients. Phys. Rev. Lett., 109:196602, Nov 2012.

    Biography

    Casey W. Miller is presently Associate Professor of Physics at the University of South Florida in Tampa, where he studies nanoscale magnetism and related devices. He is Director of the new APS-Bridge Site at USF, as well as Associate Director of Physics Graduate Studies. He graduated summa cum laude from Wittenberg University in 1999 with University and Physics Departmental Honors and, where he was also elected to ΦΒΚ. He earned his PhD from the University of Texas at Austin in 2003, notably earning the Department’s Best Dissertation Award for work combining Magnetic Resonance Imaging with Scanning Probe Microscopy. He joined USF in 2007 after completing a post-doctoral fellowship at the University of California, San Diego, where he worked on spin-dependent tunneling.

  • AFM force measurements of ligand-receptor interaction

    Sept. 27, 2013, 1:30pm-2:30pm, OE 134

    Dr. Vincent T. Moy Professor of Physiology & Biophysics Department of Physiology & Biophysics School of Medicine, University of Miami

    Abstract:

    My laboratory is interested in understanding how weak intermolecular forces generated by the interactions of biomolecules contribute to cellular functions. Our experimental approach involves the acquisition of direct measurements of intramolecular and intermolecular forces at the level of individual molecules. Thus, an important component of my research is the development of advanced biophysical techniques with the sensitivity and precision to investigate the submicroscopic properties of biological systems under near physiological conditions. One such technique employs the atomic force microscope (AFM) to measure the mechanical forces generated during cell adhesion and migration. This talk will summarize advances in AFM force measurements of ligand-receptor interaction for single molecule and cell adhesion studies.

    Biography:

    r. Vincent T. Moy is currently a professor in the Department of Physiology & Biophysics at University of Miami medical school. He is interested in understanding how weak intermolecular forces generated by the interactions of biomolecules contribute to cellular functions. He received his B.A. in biophysics/Math from University of Pennsylvania in 1984, and his Ph.D. in chemical physics from Stanford University in 1988. He received postdoc training in Biochemistry at the University of UC San Diego from 1988 to1993. Before joining University of Miami in 1995 as an assistant professor, he worked as an assistant in Physics at Technical University Munich at Germany.

  • Femto-fast and Nano-small: Ultrafast Spectroscopy of Semiconductor Nanostructures

    Sept. 20, 2013, 1:30pm-2:30pm, OE 134

    Dr. Hebin Li, Assistant Professor in the Department of Physics at Florida International University

    Abstract

    Semiconductor nanostructures such as quantum wells, quantum wires and quantum dots have increasing number of applications in the fields of science, technology and medicine. Some critical material properties including optical responses strongly depend on the many-body states of carriers and their dynamics. The characteristic time scale of the carrier dynamics ranges from a few femtoseconds to hundreds of picoseconds. Femtosecond lasers provide unprecedented time resolution to study the carrier dynamics in such materials. One of the advanced ultrafast spectroscopic techniques is Optical Multi-dimensional Fourier Transform Spectroscopy. The concept of multi-dimensional Fourier transform spectroscopy originated in nuclear magnetic resonance (NMR) where it revolutionized NMR studies of molecular structure and dynamics and led to the Nobel Prize in Chemistry in 1991. In the past decade, the same concept has been implemented in the optical region with femtosecond lasers. In this presentation, I will introduce Optical Multi-dimensional Fourier Transform Spectroscopy and its applications to study dynamics of quantum systems. Both 2D and 3D spectra of a potassium atomic vapor will be presented as a test case to validate the method. I will then present the use of multi-dimensional spectroscopy to study many-body states and carrier dynamics in semiconductor quantum wells and quantum dots.

    Short bio:

    Hebin Li is currently an assistant professor in the Department of Physics at Florida International University. He studies the interaction of light with matter by using cutting-edge optical tools. He is particularly interested in many-body quantum systems consisting of interaction atoms, molecules and electrons. He develops and uses techniques and ideas in ultrafast spectroscopy and quantum optics to probe and manipulate quantum dynamics of such systems. He received his B.S. in physics from Wuhan University in 2001, and his Ph.D. in physics from Texas A&M University in 2010. Before joining the faculty at FIU in 2013, he worked as a Research Associate at JILA, a joint institute of the National Institute of Standards and Technology (NIST) and the University of Colorado at Boulder. For more information, please visit his website at faculty.fiu.edu~hebin.

  • Mass Spectrometry based bio-imaging: Current challenges and perspectives

    Sept. 13, 2013, 1:30pm-2:30pm, OE 134

    Dr. Francisco Fernandez-Lima, Department of Chemistry and Biochemistry, Florida International University

    Abstract

    he characterization of biological systems requires the knowledge of their chemical constituents, locations, and dynamics. Mass spectrometry (MS) provides unrivaled capability for the detection, characterization and identification of a large number of analytes (e.g., hundreds to thousands) in a single experiment from an in vivo, in vitro or in situ tissue section. Mass spectrometry based imaging (MSI) combines the capabilities of modern MS with imaging; that is, MSI provides the distribution and localization of different analytes in a tissue without the need for apriori selection of the analyte of interest. There are two main challenges in the molecular characterization of native surfaces using MSI: the quantity of sample available for analysis and their dynamic range. In the present talk, a suit of MSI variants, their current state-of-the-art and challenges will be discussed. In particular, current efforts at FIU for the characterization of the chemical environment at the single cell and sub-cellular level of model cell systems and tissue sections using a “molecular microscope” will be described.

    Biography

    Dr. Fernandez-Lima is a NIH R00 fellow with a research focus on the development of new generation instrumentation and methodologies for biomedical and behavioral research. He received a Ph.D. on Applied Physics from the Pontific Catholic University of Rio de Janeiro, Brazil, with his work on the study of laser and ion induced molecular desorption for the analysis of biological samples using mass spectrometry. He has worked on a variety of surface characterization and biological mass spectrometry projects at Texas A&M University (Dr. David H. Russell and Dr. Emile A. Schweikert groups) and he is also a research fellow of Bruker Daltonics Inc. Life Science division. He has authored over 50 peer-reviewed scientific publications and review articles, and actively presents his work at national and international conferences. He joined the Department of Chemistry and Biochemistry at Florida International University in the summer of 2012 and is the Director of the Advance Mass Spectrometry Program.

  • Catalytically Etching Graphene and Graphite by Metal Particles

    Sept. 6, 2013, 1:30pm-2:30pm, OE 134

    Dr. Irene Calizo, Department of Electrical and Computer Engineering, Florida International Univers

    Abstract: Graphene stands as a promising material for future nanoelectronics owing to a slew of exotic properties such as micron scale ballistic transport at room temperature, extremely high thermal conductivity, and very high current carrying ability. Future applications necessitate graphene configurations with a particular shape and edge. Metal nanoparticle (NP) etching has emerged as a promising solution for etching graphene along specific crystalline directions. In this work, graphene and graphite etching by metal particles is characterized using low-voltage scanning electron microscopy (LVSEM), optical microscopy, and Raman spectroscopy. Two particle systems are presented, Fe and Cu. LVSEM, utilizing both the SE2 and Inlens detectors, reveals different morphology for the Cu and Fe particles and different etching behaviors due to their distinct interactions with carbon.

    Biography: Dr. Calizo is an assistant professor in the Department of Electrical and Computer Engineering at Florida International University with a joint appointment in Mechanical and Materials Engineering. She received her Ph.D. in Electrical Engineering from the University of California Riverside. She was awarded a National Research Council Research Associateship at the National Institute of Standards and Technology prior to her arrival at FIU. Her interests include two dimensional nanomaterials, carbon electronics, and defect science and engineering in nanomaterials. She currently teaches a Nanoelectronic Materials and Introduction to Nanomaterials courses. Her previous investigations included the thermal properties of graphene and more recently she has been looking at etching graphene by metal particles.

  • Radiomicrosphere Therapy for Liver Cancer

    Aug. 30, 2013, 1:30pm-2:30pm, OE 134

    Dr. Anthony Mcgoron, Biomedical Engineering, Florida International University

    Yttrium-90 (Y-90) microsphere radioembolization, known as Selective Internal Radiation Therapy (SIRT), via hepatic arterial administration is a treatment for patients with primary and metastatic liver cancer because the primary blood supply to liver tumors is from the hepatic artery while the majority of the blood supply to the normal liver is from the portal vein. The micro-vascular density of liver tumors is 3-200 times greater than the surrounding liver parenchyma further improving the selectivity of the therapy to the tumor. In this treatment, 30 μm diameter spheres labeled with the radioactive isotope Y-90 (a high-energy beta particle–emitting radioisotope) become lodged in the arterioles within the tumor and destroy the tumor while leaving the normal liver tissue mostly unharmed. For treatment planning Tc-99m-macro aggregated albumin (MAA) is infused into the proper hepatic artery and a perfusion scintigraphy is performed. However, the significant difference in size, shape, and other properties of the MAA and the Y-90 microspheres complicates the treatment planning because the MAA particles cannot be expected to distribute the same as the Y-90 microspheres. Thus it is desirable to develop and use a new biodegradable sphere for accurate SIRT planning. The production and in vitro evaluation of various polymers (PGCD, CHS and CHSg) microspheres for a RMT and RMT planning will be described. For imaging, the particles are labeled with 68Ga or 99mTc. Microparticles with a 30±10 μm size distribution are prepared by emulsion method. The in vitro half-life of the particles is determined in PBS buffer and porcine plasma and their potential application (treatment or treatment planning) established. Studies are also done in rats and mice to determine in vivo labeling stability and microsphere degradation rate. Numerical dosimetry calculations are done to evaluate the radiation field and dose distributions and assure radioprotection standards are met.

  • Microfluidic selection strategy targeting the excited-state dynamics of fluorescent proteins

    April 19, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. Ralph Jimenez, JILA and Department of Chemistry & Biochemistry, University of Colorado and NIST, Boulder, CO.

    Abstract:

    Genetically encoded fluorescent proteins (FPs) have enabled explorations of cellular dynamics with unprecedented spatio-temporal resolution. Compared to the best fluorescent dyes, however, the complex excited-state dynamics of FPs result in ~100-fold accelerated photobleaching and dark state conversion. These properties limit the imaging duration and signal output in fluorescence microscopy and compromise the widespread use of FPs in single-molecule or low-copy fluorescence imaging. We developed a cell-based library screening method to improve the photophysics of FPs with a microfluidic cell sorter that measures fluorescence photobleaching characteristics of individual cells. Viable cells retrieved from a sort can be used either in subsequent rounds of screening, or these clones may be mutated further (i.e. enabling “directed evolution.”)

    We demonstrate this selection approach on a >105 member saturation mutagenesis library of the mCherry chromophore environment in a region where computational studies predict the presence of thermally accessible pathways for O2 entry to the chromophore. Multiple rounds of selection on this library have enabled the isolation of new clones with improved photostability. Finally, we have integrated phase-fluorometry capabilities into the instrument, which will enable cell sorting on the basis of both photobleaching and fluorescence lifetime. Our approach will not only enable the creation of new generations of FPs with excited-state dynamics optimized for brighter, long-duration imaging, but it can also be extended to enable development of FPs for novel imaging modalities.

  • The Higgs Boson

    April 12, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. Jorge Rodriguez, Department of Physics, Florida International University

    Abstract:

    Recent, within the last month, new results on the Higgs boson were released to the public by ATLAS and CMS. The results reported an update to the measured mass of a Higgs-like particle, decay rates of this new particle to standard model particles and summarized what is currently known about this Higgs-like discovery first reported on July 4th 2012. The interest in the Higgs is motivated in part by what is typically stated regarding the Higgs, basically "the Higgs gives mass to all fundamental particles", usually without further elaboration. In this talk I will elaborate on the meaning of this statement detailing from first principles how the masses are "given" to the fermions, and gauge bosons in the standard model, going beyond the usual one sentence assertion. I will start from the symmetry principles that motivates the introduction of a Higgs field describe why it is needed an how it actually does "generate mass for all the particles". This will be done in the context of the Standard Model of particle physics. I will also summarize, briefly the latest results from the complete 2009-2012 dataset accumulated at the LHC with the CMS detector.

  • Micro-Variability in Turbulent Blazar Jets

    April 5, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. James Webb, Department of Physics, Florida International University.

    Abstract:

    We present an update on the SARA Consortium, including the status of the two current telescopes and the possible addition of a telescope in the Canary Islands. We will then present a summary of the 15 project to study micro-variability in Blazars. The culmination of that study is a model for Blazar Micro-variability where the rapid, low amplitude fluctuations are the result of a shock passing through a turbulent section of the relativistic jet. As the shock encounters the turbulent cells, the plasma in the cells is accelerated and emit a pulse of Synchrotron emission. We show several well sampled micro-variability curves de-convolved and our model applied to determine the distribution of cell sizes and other physical parameters of of the turbulent flow.

  • Nanomaterials: Discovery and Integration at CINT

    March 29, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. Neal Shinn, Co-Director, DOE Center for Integrated Nanotechnologies (CINT) Sandia National Laboratories Albuquerque

    Abstract:

    Interest in nanoscience—and derivative nanotechnologies—has grown explosively because of the perceived potential to beneficially impact almost every aspect of our lives. The fascination with nanostructured materials and interest in their unique, size-dependent properties will fade quickly if these novel materials cannot be exploited in new technologies. Hence, we are challenged not only to create, characterize and understand nanostructured materials in isolation, but also to learn how they will perform when integrated with other materials. As a DOE Office of Science National User Facility, the Center for Integrated Nanotechnologies (CINT) provides expertise and capabilities to hundreds of researchers annually. In this presentation, I will use CINT research highlights including nanowires, nanomechanics, nanophotonics and composite materials to illustrate the CINT capabilities available to future CINT users for their own nanoscience research.

    This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. Department of Energy, Office of Science user facility operated jointly by Los Alamos and Sandia National Laboratories. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000.

    Bio:

    Neal D. Shinn, Ph.D. Co-Director DOE Center for Integrated Nanotechnologies Sandia National Laboratories Albuquerque, NM 87185-1315 ndshinn@sandia.gov

    Dr. Shinn is the Co-Director for the Center for Integrated Nanotechnologies (CINT), a nanoscience user facility jointly operated by Los Alamos and Sandia National Laboratories for the U. S. Department of Energy’s Office of Science. He received the B.S. degree in Chemistry and Mathematics from the Pennsylvania State University in 1978 and the Ph.D. degree in Chemical Physics from the Massachusetts Institute of Technology in 1983. Thereafter, he was a National Research Council Post-Doctoral Fellow at the National Institute of Standards and Technology, where his research involved the elucidation of surface reaction intermediates using vibrational and electronic spectroscopies in conjunction with thermal and stimulated desorption. In 1985, he joined Sandia National Laboratories as a Senior Member of the Technical Staff, later becoming the Manager of the Surface and Interface Science Department. Dr. Shinn’s research interests involve the physics and chemistry at solid surfaces. He has published over 85 scientific papers, serves on DOE and academic advisory boards, and was the 2007 President of the AVS Science & Technology society.

  • The Nucleus at Short Distances

    March 22, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. Wim Cosyn, Ghent University, Belgium

    The nuclear shell model has been and still is an invaluable tool in our understanding of nuclei. It describes the nucleus as a collection of protons and neutrons moving in an average potential created by the strong interaction between these nucleons. Since the advent of quantum chromodynamics, however, we know that quarks and gluons make up the fundamental degrees freedom of the strong force. At nucleonic length scales these quarks and gluons are confined in colorless hadrons, which emerge as the effective degrees of freedom. How and when this transition happens, is still an outstanding problem that attracts great research interest.

    Another limitation of the nuclear shell model is the presence of a hard core in the nucleon-nucleon potential. This hard core induces so-called short-range correlations which cause high density fluctuations in the nucleus.

    One way of exploring these phenomena and advancing our knowledge about them, is using high-energy reactions with nuclear targets. When dealing with nuclear targets one has to take into account the interactions of the particles with the nuclear medium. These are called final-state interactions. This seminar will illustrate how final-state interactions and short-range correlations are used and dealt with in theoretical calculations and experiments carried out at high-energy nuclear facilities such as Jefferson Lab.

    Short-Bio:

    05/2009: Ph.D in Sciences: Physics, Ghent University. 07/2004: Master of Science in Engineering: Physics, Ghent University. Finished summa cum laude

    Oct 2009-Present: FWO (Research Foundation – Flanders) grant post-doctoral researcher at Ghent University

    Feb 2010-Apr 2011: Visiting post-doctoral researcher at Florida International University with a FWO mobility grant and support from the faculty of sciences of Ghent University

    Oct 2006-Sep 2009: FWO (Research Foundation – Flanders) grant PhD-Fellow at Ghent University

    Oct 2004-Sep 2006: BOF (Bijzonder Onderzoeksfonds) grant PhD-Fellow at Ghent University

  • Harvest of solar light to electricity with advanced nano-structured materials

    March 8, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. Mengjin Yang Florida International University

    Abstract:

    Solar energy is an abundant, clean, and long-lasting energy, and it is pivotal to collect such the gigantic energy efficiently in order to satisfy ever-growing globe energy demand. A broad review on the current development of solar cell, which converts solar light directly to electricity, will be given, from fundamental operation principles, cost analysis, to different implemented technologies. The roles of nano-structured materials in novel solar cells will be delineated especially for sensitized solar cell. Construction of heterojunction with intrinsic thin layer, silicon nanowire, various nanostructures of metal oxide photoanodes (nanoparticles, nanotube, nanowire/nanorod, inverse-opal, aggregate), and their effects on interfaces, carrier transport, and light path will be discussed. The successful integration of nanostructured materials will drive solar cells to the low-cost, high efficiency, and eventually widely deployment.

    Short bio:

    Dr. Yang is currently a postdoc research associate in Physics at Florida International University. He received his Ph.D in materials science from the University of Pittsburgh in 2012. His research interests are in 1-dimentional nanostructure materials for optoelectronics, solution processed solar cell, hybrid solar cell, functional oxide materials, and carbon materials.

  • An Engine for STEM Education Reform

    March 1, 2013, 1:30pm-2:30pm, AHC3 205

    David Hestenes, Director, Science Modeling Institute, Emeritus Professor of Physics, Arizona State University

    Abstract:

    Rapid emergence of a global economy driven by science and technology has precipitated a crisis in the U.S. education system. Cries of alarm continue to echo throughout the news media as U.S. education falls further and further behind –– not only behind the pace of technological change, but also the educational performance of other countries. In response, a national consensus has emerged calling for comprehensive K-12 STEM education reform. However, the U.S. education system, with critical functions and responsibilities dispersed among schools, school districts, colleges of education and government agencies, has proven to be too ponderous and unfocussed to enact timely, significant reform. Briefly put, our education system lacks institutional mechanisms for rapid adaptive change. Ultimately, all reform is local. Therefore, the key to education reform is empowering teachers as agents of change. We discuss how the STEM education crisis can be addressed by incorporating this principle in the design of a robust engine to drive rapid, deep and sustained STEM education reform nationwide.

  • How Do Carbon Nanotube Fibers Gain Their Strength?

    Feb. 22, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. Tsu-Wei Chou Center for Composite Materials and Department of Mechanical Engineering, University of Delaware

    Abstract:

    The potential of translating the superb mechanical and physical properties of individual carbon nanotubes (CNTs) at the nano-scale to the macro-scale of continuous fibers is fascinating and has driven considerable research interest in the past decade. From the viewpoint of reinforcements for fiber composites, the potential for using CNTs in a continuous form would enable their adaptation to many well-developed composites processing, characterization and micromechanics methodologies. Even though very high strengths and moduli for CNT fiber have been reported in the literature, the processing of high performance CNT fibers with consistent, reproducible quality remains elusive. This presentation is intended to introduce our current research, the aims of which are two-fold. First, a concerted effort has been made to assess the status of CNT fiber technology by examining fibers from various sources based on different processing methods. Research results in characterizing the tensile, compressive, torsion, as well as electromechanical behaviors of CNT fibers will be reported. Through our characterization studies, a more comprehensive knowledge-base of CNT fiber has emerged. This research has fueled the question, "How do CNT fibers gain their strength?". Therefore, our second initiative is focused on identifying key contributing factors affecting the mechanical properties of CNT fibers. Preliminary research results based upon the coarse-grained molecular dynamics in modeling the influence of these factors, such as CNT length, CNT entanglement, intertube interactions, as well as the fiber twist angle, will be reported. The combined experimental and analytical effort will eventually enable the optimal design of CNT fibers for high performance composite applications.

    Bio:

    Dr. Tsu-Wei Chou is the Pierre S. du Pont Chair of Engineering at the University of Delaware. He received the Ph.D. degree in materials science from Stanford University. Dr. Chou's research interests are in materials science, applied mechanics, fiber composite materials, piezoelectric materials, and nanocomposites. He has authored over 330 archival journal papers and book chapters in these areas. He is the author of the book, Microstructural Design of Fiber Composites, Cambridge University Press, England (1992), the co-author of the book, Composite Materials and Their Use in Structures, Elsevier Applied Science, London (1975), and the editor of several books. Dr. Chou is a Fellow of ASME, ASM, ASC, ACerS, TMS and AIAA, and a recipient of the Charles Russ Richards Memorial Award and the Worcester Reed Warner Medal of ASME, the Distinguished Research Award of American Society for Composites, and the Francis Alison Medal as well as the Medal of Excellence in Composite Materials of the University of Delaware. Dr. Chou is the Editor-in-Chief of the international journal Composites Science and Technology. He has been recognized by ISI as one of the "Highly Cited Researchers" in the world. Dr. Chou has been named among top 100 materials scientists (ranked 34th) of the past decade (2000-2010) by Times Higher Education, and is honored as a World Fellow by the International Committee on Composite Materials.

  • Non- existence of certain Einstein metrics on some symplectic manifolds

    Feb. 15, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. Augustin Banyaga, Mathematics Department, Pennsylvania State University

    e exhibit a necessary and sufficient condition for a symplectic manifold $(M, \omega)$ to admit an $\omega$- compatible Einstein metric. This research was motivated by the Goldberg conjecture asserting that a compact symplectic manifold $(M,\omega)$ with an $\omega$- compatible Einstein metric is Kaehler. This is a joint work with F. Massamba.

    Brief biographical sketch:

    Augustin Banyaga is a Professor of Mathematics at Penn State University, University Park. His research areas are in Symplectic, Contact Geometry and Topology, and Morse Theory ( Morse Homology, Morse-Bott homology). Lately he has worked on the foundations of the $C^0$ symplectic Topology and the Hofer Geometry. Augustin Banyaga is a Fellow of the African Academy of Sciences

  • Neutral Atom Analogs to Basic Electric Circuit Elements

    Feb. 8, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. Wendell Hill Joint Quantum Institute, Department of Physics and Institute for Physical Science and Technology University of Maryland

    Abstract:

    Atomtronics, a relatively new field of physics, seeks to re-engineer electronics where atoms are the basic carriers of information. Today, electronics only exploits the charge of the electron; it is becoming more and more clear, however, that simply utilizing the spin of the electron would enable novel ways to store information. Devices based on so-called spintronics have the potential to revolutionize electronics. The atom, having a more complex internal structure than the electron, makes the possibilities with atomtronics far richer than those with spintronics. Crossed laser beams, producing optical lattices, and lasers with exotic spatial distributions, such as higher order Laguerre-Gauss modes, provide a means for establishing optical dipole potentials that have lead to several cold atom-based analogs to electronics and condensed states of matter. Persistent currents in a ring, a close atom analog to a superconducting circuit, and even a Josephson junction are just two examples of circuit analogs that have been demonstrated. While these harmonic potentials have received the most attention, arbitrary, non-harmonic potentials would allow a host of new analogs to be constructed, including more basic electrical elements. Exploiting an adaptation of a generalized phase-contrast approach, we have generated high-quality two-dimensional (2D) optical patterns that are ideal for creating low-noise potentials for neutral atoms – free-space atom chips. The chip is composed of an etched “light substrate” – a 2D sheet of light that is either red or blue detuned from the atomic resonance. The substrate is etched by the spatially-shaped beam propagating in a direction orthogonal to the plane of the sheet, which can be either red detuned or blue detuned as well. In contrast to the more familiar material-based atom chips, free-space atom chips can possess potentials that are non-harmonic, have sharp walls and barriers that can even be modified on a timescale commensurate with the flow of an atomic BEC. We have taken the initial steps toward realizing these chips by creating RLC circuits, the resistance and inductance of which are equivalent to the Sharvin (ballistic) resistance in metals and the usually small kinetic inductance, respectively. Similarly, the capacitance is related to the imbalance between the number of atoms and the chemical potential between two points in the circuit. To our knowledge, this is the first demonstration of an atomtronics circuit with analogs to basic elements of an electronic circuit and the first direct observation in real time of the flow of an ideal gas through a channel.

    Bio:

    Wendell T. Hill, III holds the rank of Professor at the University of Maryland, College Park, with appointments in the Institute for Physical Science and Technology and the Department of Physics and is also a fellow of the Joint Quantum Institute (JQI). He earned his BA from the University of California, Irvine, in 1974 and his PhD from Stanford University in 1980, both in physics. He is a guest worker at National Institute for Standards & Technology (NIST), where he was a postdoc before joining the faculty of the University of Maryland in 1982, as well as a visiting scientist at Lawrence Livermore National Labs. He has held visiting positions with Instituto Venezalano de Investigaciones (Venezuela), Université de Paris-Sud, (Orsay, France) and JILA at the University of Colorado. Hill’s honors include Fellow of the American Physical Society (APS), Fellow of the National Society of Black Physicists, Presidential Young Investigator of the National Science Foundation (NSF) and has been profiled by the History Makers. Hill’s research interests are broad with publications ranging from high-energy particle physics to ultracold atoms; he has wrote the introductory chapter on electromagnetic radiation for the Encyclopedia of Applied Spectroscopy, published in 2009 by Wiley and is the co-author of the physics text Light-Matter Interaction: Atoms and Molecules in External Fields and Nonlinear Optics, published in 2007 by Wiley. His current investigations fall into three areas within atomic, molecular and optical (AMO) physics: (1) ultrafast dynamics and quantum control; (2) ultraintense laser-matter interaction and high-energy density physics; and (3) atomtronics and quantum information science. Hill has been a member of and chaired numerous program committees for national and international conferences, has served on several committees (some of which he also chaired) for the APS, the Optical Society of America (OSA), the National Academy of Sciences (NAS) and NSF, and has served as the program officer for the $20M AMO program at NSF (2010-2012 academic years). He has also been instrumental in production of reports for the NAS, APS and NSF promoting physics and community action for improved health of physics (AMO in particular) in the US as well as the engagement of more members of underrepresented groups in physics, all while teaching and pursuing research within the JQI at the University of Maryland.

  • Plasmonics: science and technology of surface plasmons

    Feb. 1, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. Krzysztof Kempa, Department of Physics, Boston College

    Abstract:

    Surface plasmons, predicted by Rufus Ritchie in 1957 are the key ingredient of plasmonics, and have led in recent years to numerous applications, ranging from optics to medicine. A brief historical background of the pre-surface plasmon plasmonics, and its connection to plasma and particle physics will be followed by a discussion of the various surface plasmons at metallic surfaces. It will be shown how understanding of the electromagnetic response of nanostructures and metamaterials can benefit from earlier studies of plasmons in the semiconductor heterojunctions, quantum wells, and quantum dots. I will also discuss briefly the response of graphene, as well as carbon nanotubes, with their numerous van Hove, 1D, 3D plasmons, as well as plasmarons.

    Short bio:

    Dr. Krzysztof Kempa received his Master of Science degree from the Institute of Electron Technology of the Technical University in Wroclaw (Poland) in 1973, and the PhD degree from the University of Wroclaw in 1980. Presently a Full Professor of Physics at Boston College, he co-authored over 100 peer reviewed papers, gave over 40 invited talks and seminars, and has over 10 patents in the field of semiconductor devices, nano-optics, and photovoltaics. His Visiting Professor appointments included the Free University Berlin (Germany), Technical University of Vienna (Austria), and the Imperial College in London (England). Currently, he is a Distinguished Visiting Professor at the South China Normal University in Guangzhou (China). He co-organized the NT02 International Conference on Science and Applications of Nanotubes, Boston 2002, and co-founded NanoLab, Inc., a nanotech company which manufacturers carbon nanotubes and related products (www.nano-lab.com). His research interests are in the field of plasmonics, nano-photovoltaics, and metamaterials.

  • Λ photoproduction on a deuteron at threshold energies

    Jan. 25, 2013, 3pm-3:50pm, CP 107

    Brian O. Beckford Department of Physics, Tohoku University

    Abstract:

    The research that has been my focus as a PhD candidate at Tohoku University is Strangeness physics. The aim of the study was to measure the generation of “strange” particles, of which emphasis was placed on one named Λ, by a high-energy photon. In this brief talk I will give a general introduction to nuclear physics and the motivations for such a study. This will be followed by an overview of the experiment and a few results.

    *

    Brief biographical sketch:*

    Brian O. Beckford is a Ph.D. student in physics at Tohoku University, with M.S. and B.S in physics from Florida International University. He has been active in organizations such as the Society of Physics Students, and was awarded the Super Doctor Fellowship to study in Japan. As undergrad at Florida International University also he participated in the Ronald E. McNair Post Baccalaureate Fellowship

    Brian currently preparing for his PhD defense, avidly training in Japanese arts (Kendo and Iaido), and has recently been consolidating his writings into a collection named “Unforeseen Meditations”.

    Brian is originally from Jamaica, but was raised in Miami, Florida. His interests include spending time reading philosophy and poetry, pencil drawing, cycling, and plans to enter into the Ironman triathlon in the future along with Alejandro De la Puente.

  • Biophysics and Bioelectronics for Theranostics

    Jan. 25, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. Chengzhong Li, Associate Professor, Nanobioengineering/Bioelectronics Lab, Department of Biomedical Engineering, Florida International University

    Abstract:

    Theranostics is referred to as a treatment strategy that combines therapeutics with diagnostics, aiming to monitor the response to treatment, which would be a key part of personalized medicine and require considerable advances in predictive medicine. This research area is a rapidly progressing interdisciplinary research field that is based on the cooperative work of chemists, physicists, biologists, medical doctors and engineers. For diagnostics, biosensors are one of the most attractive approaches for rapid, accurate and sensitive diagnostics, especially for point of care testings. As for therapeutics, non-invasive therapy including electrical therapy and magnetic therapy recently has made significant progress based on the deep understanding of biophysical and bioelectrical properties of biomolecules and the development of nanotechnology and fabrication technology. The unique electronic, optical and catalytic properties of engineered nanoparticles including carbon nanotubes, graphene, metallic nanoparticles, etc pave the way to new applications particular in medicine and pharmacology. On the other hand, various biomolecules exhibit the unique biological properties such as bio-recognition, self-assembly properties. In my lab, we are integrating the physical and chemical properties of nanomaterials and the biological properties of biomolecules with MEMS technology and analytical systems to develop highly sensitive miniaturized devices for biomedical sensing and noninvasive medical therapy. This lecture will outline our recent research activities for the fundamental study of physical and electrical properties of biomolecules such as cells, as well as the development of a new generation of micro/nano biosensors that combine aspects of “top-down” nanofabrication approach with a “bottom-up” self assembly method. Several newly developed biosensors will be introduced including: 1) Cell Impedance and SPR biosensors for real time whole cell analysis and cell manipulation. 2) Paper based strips for telemedicine and point of care testing (POCT). .

    Bio:

    Prof. Chenzhong Li earned his M.Sc in electrochemistry and PhD in bioengineering from Kumamoto University (Japan) in 1996 and 2000. Before joining FIU in 2006, he held a position as a Research Officer at the Nanobiotechnology lab in the Canada National Research Council (Montreal). Currently he is a tenured associate professor in the Department of Biomedical Engineering at Florida International University. Dr Li’s research has focused primarily on the clinical point-of-care, biodefense and environment related applications of bioelectronic sensing technology. His research activities to date have resulted in 5 patents, 68 peer-reviewed journal papers and proceedings (H-index 19 by 2012), 2 books and 4 book chapters, over 110 presentations at conferences including about 73 keynote/invited lectures and seminars worldwide. In addition to his publication activities, he is the guest editors of American Journal of Biomedical Science, and the Journal of Neuroscience and Neuroengineering. He is the associate editor of the journals of Applied Biochemistry and Biotechnology, Chemical Sensors and Biosensors Journal. He is an academic editor of PLoS ONE. He also serves on several journal editorial boards as well as being a reviewer and panelist for NIH, NSF and NSERC (Canada). In recognition of his work, Dr. Li has received several awards and honors including the Japanese Monbusyo Fellowship, the FIU faculty research award (2008), the Kauffman Professor Award in 2009 and 2011 and 2013 Japanese JSPS fellow

  • Controlling and measuring the energy landscape in single semiconductor nanowire heterostructures

    Jan. 18, 2013, 1:30pm-2:30pm, AHC3 205

    Dr. Leigh Smith, Department of Physics, University of University of Cincinnati

    Abstract:

    There has been intense interest in recent years to control the electronic structure in quasi one-dimensional nanowires through the fabrication of novel axial and radial heterostructures. Unlike materials in higher dimensions, nanowires have the unique ability to grow axial or radial heterostructures between almost any two materials regardless of lattice mismatch or strain. Understanding exactly how the electronic properties of the nanowire are changed through this control is extremely important and requires spectroscopies with high spatial, temporal and spectral resolution. I will discuss a number of examples in which the electronic structure in nanowire heterostructures can be modified either through strain, crystal structure, or quantum confinement, and what insights can be provided by a number of single nanowire optical spectroscopies.

    Transient Rayleigh Scattering: A new probe of picosecond carrier dynamics in a single semiconductor nanowire, M. Montazeri et al, Nano Letters 12, 5389-5395 (2012).

    Direct imaging of the spatial diffusion of excitons in single semiconductor nanowires, M.A. Fickenscher et al. Applied Physics Letters, 99, 263110 (2011).

    Photomodulated Rayleigh Scattering of Single Semiconductor Nanowires: Probing Electronic Band Structure," M. Montazeri, et al, Nano Letters, 11, 4329-4336 (2011).

    Direct Measure of Strain and Electronic Structure in GaAs/GaP Core-Shell Nanowires, Mohammad Montazeri, et al., Nano Letters, 10, 880-886 (2010).

  • Flipping the Classroom in an Algebra-based Physics Course at an Urban University

    Jan. 17, 2013, 2pm-3pm, AHC3 205

    Dr. Leigh Smith, Department of Physics, University of University of Cincinnati

    Abstract:

    A significant fraction of contemporary students at state-supported universities suffer from two distinct stresses: Their background in Mathematics can be remarkably weak, and at the same time students work significant hours to support themselves and to make up the difference between rising tuition costs and the limits on Federal student loans. The combination of both of these issues simultaneously can result in disastrous affects on student learning in a formal course in physics. In this talk I will describe two approaches to confront these issues head on in a formal algebra-based physics course. The algebra-based physics course is taken mainly by students in the biological sciences or pre-professional programs (pre-medical, pre-pharmacy or health-related professions such as physical therapy, medical imaging or nutrition) who are required to do well in order to proceed academically. To mitigate weak mathematics skills we have made available to all students in the five weeks preceding the Fall term each year the online mathematics tutorial system, ALEKS (www.aleks.com). ALEKS is a self-paced adaptive mathematics learning system which covers algebra, geometry, trigonometry and vectors up through pre-calculus. Significant gains in success rates have been documented over the past three years for those students who worked with ALEKS before classes start versus those with similar backgrounds who did not use the online tutorial system. To mitigate the problem of significant work schedules, we have introduced a flipped classroom model. In the flipped classroom approach, students work through extended readings combined with conceptual multiple choice tests and video tutorials in the four days before class each week. The class meets twice per week in a large tiered classroom of 135 seats. In the class the response system Learning Catalytics (learningcatalytics.com) is used to guide randomized groups of 5 students through solutions on representative homework problems. Over two years, we have made direct comparisons on formal tests between 459 students taking the flipped classroom model, and 1158 students who are in a standard lecture. All students take common midterms and final exams which make direct comparisons straightforward. Significant gains in success rates have been documented for students who are in the flipped-classroom model versus those students who are in standard lecture classes. Through combination of these two approaches the DWF (non-success) rates for all students have fallen from 35% to 25%, while the flipped classroom approach has reduced the DWF rate to below 15%.