Syracuse University
CONDENSED MATTER and BIOLOGICAL PHYSICS
Faculty
Mark Bowick is a
theoretical and computational physicist who works at the "triple-point"
of elementary particles, gravitation, and condensed matter. Two
aspects of his work which relate to condensed matter physics are:
· Computational and analytical studies of the properties of membranes and random surfaces; recent work has revealed a tubular phase transition in anisotropic membranes.
· Experimental and theoretical studies of topological defect formation during the isotropic to nematic phase transition in liquid crystals; these string defects are a laboratory analog for cosmic string formation during the colling of the early universe.
Professor Bowick is co-investigator of the
theoretical particle physics grant from the Department of Energy and is
principle investigator on a National Science Foundation Information
Technology and Research grant "Statistical
Physics and Computational Complexity", through the Division of Matierals
Research.
Kenneth Foster and Jureepan Saranak's overall research goals are to understand
how biological sensors -- in particular light sensors --work, and how
they have evolved over the last few billion years on Earth. We
are studying model cell systems from three major biological Kingdoms:
· the Green Alga, Chlamydomonas reinhardtii
· the Fungal zoospores of Allomyces reticulatus, and
· the Stramenopiles, Mallomonas and Fucus sperm.
Various aspects are under investigation at different biological levels. For example, for unicellular vision we are studying the architecture of its light capturing structure, a dielectric antenna or eye. At the cellular level, the nonlinear ciliary responses that enable the cell to use its eye to track the direction of light are being analyzed. At the intermolecular level, we are employing systems analysis to describe the network of sensory signals within a single cell. Some of these signals come from light receptors at the eye and are used to steer the cell with its cilia. At the molecular level, we are studying how the light receptor molecules work. Specifically, we seek the mechanism of activation of the rhodopsin and other G-protein-activating receptors is being sought. With the conservation of nature, hundreds of different receptors in human would appear to be in the same superfamily, first evolved 3.5 billion years ago.
Techniques developed for this work are also being applied, in collaboration with others, to understand the ubiquitous pathways by which light can control of gene expression.
Professor Foster is principal investigator (with professors Lipson and Saranak) of the grant "Nonlinear Dynamics of Cellular Signal Transduction" from the National Institutes of Health.
Arnold Honig's laboratory
has worked primarily in two fields: experimental semiconductor physics
(with an emphasis on the persistent photoconductivity effect
found in GaAs, CdS, and other semiconductors), and the production and
characterization of nuclear spin polarized hydrogen-deuteride (HD).
This unique material is prepared at Syracuse under extreme conditions
of high magnetic fields and low temperatures. The spin physics involved
in its production is fascinating, and the spin-polarized material is
used for experiments in nuclear physics and fusion. Spin-polarized HD
based on the Syracuse work is of crucial importance as the target for
upcoming experiments at Brookhaven National Laboratory. In recent years
Honig has also been working on methods for preparing "hyperpolarized"
nuclei for use in magnetic resonance imaging. There is substantial
current activity using optical-pumping methods to produce
hyperpolarized 129Xe and 3He; the cryogenic
methods developed in Honig's laboratory present an alternative to the
optical-pumping approach.
Prof. Honig (emeritus) is a recipient of the Syracuse University Chancellor's Citation for Exceptional Academic Achievement.
Edward Lipson’s
research spans three areas (one basic and two applied): a) photosensory
transduction in model microrganisms, b) human-computer interface (HCI)
technologies and distributed medical intelligence (DMI; related to
“telemedicine”), and c) medical imaging. Lipson’s basic research on
sensory transduction began with studies of an organism called Phycomyces, but in recent years has shifted to the Chlamydomonas project led by Kenneth
Foster. Professor
Lipson is co-principal investigator on the grant "Nonlinear Dynamics of
Cellular Signal Transduction" from the National Institutes of Health,
of which Prof. Foster is the principal investigator. The HCI/DMI work,
described at http://www.pulsar.org
(jointly led by David Warner MD, PhD and by Lipson), includes
development of core technology (electronic devices, sensors,
transducers, and software) for applications in disabilities,
healthcare, national security, etc. (supported by a grant from the
defense department). The main effort to date on the medical imaging
project, led by Prof. Andrzej Krol of Upstate Medical University
(Radiology) involves noninvasive nuclear medicine and magnetic
resonance
imaging approaches for diagnosis of breast cancer as noninvasive
alternatives to surgical biopsy following suspect mammograms. A related
project involves nuclear cardiology. Prof. Lipson is an adjunct
professor of Radiology at Upstate and Prof. Krol is adjunct in our
department. See http://www.ecs.syr.edu/research/imaging/.
Cristina Marchetti has recently been doing theoretical research on high-temperature superconductors, and in particular upon the magnetic flux lines which thread these new materials when even a modest magnetic field is applied. These flux line arrays are crucial to the properties of the superconductor, since their motions lead to dissipation and the decay of superconductivity. In addition to the flux line work, Marchetti has published recently on:
· Dynamical properties of dense classical liquids.
· High field transport and carrier relaxation in semiconductor heterostructures.
· Collective transport in driven, disordered systems. Flux line arrays are one example; another is charge density waves in anisotropic materials.
Professor Marchetti is principal investigator of the theoretical condensed matter physics grant "Nonequilibrium Dynamics of Disordered Condensed Matter Systems" from the National Science Foundation and co-principal investigator on a National Science Foundation Information and Technology Research grant "Statistical Physics and Computational Complexity"; she is also a Fellow of the American Physical Society.
Maxim
Marchevsky carries out
experimental work in a number of areas, including transport of magnetic
flux in superconductors and magnetic pattern formation in garnet films.
His tools include various advanced microscopes, including scanning Hall
microscopy to measure spatial variations in magnetic fields. Active
areas of research include stochastic resonance and noise measurements
in these mesoscopic systems.
Alan Middleton does
theoretical research in the areas of condensed matter and statistical
physics. Topics which he has published work on include:
· The dynamics of magnetic flux lines in superconductors
· The current-voltage characteristics in arrays of "quantum dots" (lithographically created electronic devices)
· Materials with sliding charge-density waves.
These physical systems are related in that they are examples of dynamical systems with many degrees of freedom; such systems can exhibit complex behavior and novel phase transitions.
A major focus of Middleton's work is the use of computers to understand these complicated systems. In particular, he has worked on developing algorithms and computational approaches which obtain the answers for large systems quickly. He therefore works with computer scientists on some of these problems and applies techniques developed in computer science.
Professor Middleton is principal investigator of the theoretical condensed matter physics grant "Phases and Dynamics of Disordered Condensed Matter Systems" from the National Science Foundation and a co-principal investigator on a National Science Foundation Information and Technology Research grant "Statistical Physics and Computational Complexity".
Liviu Movileanu puts
big molecules through very small pores.
Britton Plourde studies quantum coherence and vortex dynamics in microfabricated superconducting devices. These devices have features as small as 100 nm, and the measurements take place in a dilution refrigerator at temperatures near absolute zero.
Quantum coherent superconducting devices are one of the leading candidates for the building blocks, or "qubits", of a quantum computer. Such a computer would be capable of solving many problems which are intractable on even the most powerful classical computer. Plourde's research focuses on fabricating these superconducting qubits, optimizing the techniques for reading out their quantum state, minimizing the decoherence of the qubits, and developing techniques for entangling qubits together.
Vortices in superconductors exhibit a rich variety of phenomena as they interact with currents, defects, and each other. By patterning particular defect structures, it is possible to control the location and motion of these vortices. Plourde's group explores such microfabricated pinning potentials to investigate quantum coherent vortex behavior, as well vortex ratchets, which can produce directed transport of vortices in response to an oscillatory driving force.
Eric Schiff's research
primarily involves experimental study of unconventional semiconductors.
Mostly the material of interest has been hydrogenated amorphous
silicon (usually denoted a-Si:H). This material started out as a
physicist's plaything. a-Si:H was the first non-crystalline
semiconductor which had electrical properties even remotely similar to
crystalline semiconductors such as silicon or gallium arsenide, and its
structural, electrical, and optical properties are extremely
interesting. Somehow a-Si:H has now gained enormous commercial
significance: it is the basis of "active matrix" flat panel displays
used for notebook computers, and is also widely applied in inexpensive
solar cells for consumer applications and power generation.
Recently, Schiff has gotten interested in porous electronic materials. Porous silicon has the property that it emits light fairly efficiently at room temperature (single crystal silicon doesn't). Porous titania is the basis of a novel solar cell invented by O'Regan and Graetzel. Both materials behave differently than either homogeneous amorphous or homogeneous crystalline materials.
Schiff's research group has particular expertise in fundamental measurements of electron and hole mobilities, electron spin resonance measurements on defects, and electroabsorption measurements addressing the device physics of solar cells.
Professor Schiff is principal investigator of the research contract "Electroabsorption and Transport Measurements and Modeling Research in Amorphous Silicon Based Solar Cells" from the National Renewable Energy Laboratory.
Gianfranco Vidali's
research is centered on the study of physical and chemical processes
occuring at surfaces under well characterized conditions. Currently,
his group is working in two areas:
· Preparation and characterization of thin solid films in far-from-equilibrium conditions. The structure, overall morphology, and dynamics of films, from submonolayer to hundreds of layers, are studied in-situ and in real time (while growth proceeds) using He beam scattering and LEED/Auger surface probes. Most recently, his group has studied the growth of films on substrates where there is both a large lattice mismatch and also large supersaturation, which is of considerable interest for the preparation of next-generation thin film devices.
· Gas-surface interactions occurring in interstellar space. Vidali's group is investigating how molecular hydrogen, and more complex molecules, are formed in the interstellar space. In the laboratory, his group studies hydrogen recombination and hydrogenation reactions on surfaces at low temperature and under conditions mimicking the actual interstellar space environment.
Vidali's laboratory houses an atomic beam scattering apparatus which was designed and built in-house. It incorporates both helium and atomic hydrogen beam lines, one ultra-high vacuum scattering chamber, a preparation chamber, and two beam detectors. Vidali has also worked on theoretical problems related to the physical adsorption of quantum gases on surfaces at low temperature and on computer simulations of thin film growth.
Professor Vidali is principal investigator of the laboratory astrophysics grant "Energetics of Molecular Hydrogen Formation on Surfaces of Astrophysical Interest" from the National Aeronautics and Space Administration.
Marcel
Wellner is an emeritus professor who does biological physics
research in collaboration with scientists at neighboring UpstateMedical University. The research
involves the propagation of electric waves in the living heart muscle. Such
waves ordinarily occur in thehealthy heart, where they are needed
to trigger the heartbeat. Occasionally, however, waves will
propagate anomalously, therebycausing dangerous or lethal
"arrhythmias." The Upstate group studies these phenomena using observational,
experimental, computational, andtheoretical approaches. Wellner has
fruitfully applied his extensive research experience in field theory to
these effects.
Last modified August 3, 2005.