This seminar will report issues addressed at a recent conference on
graduate education in physics held January 31-February 2, 2008
http://www.aps.org/programs/education/conference.cfm

Traditional physics grading systems that assess the correctness of
solution steps give an incomplete description of a student’s skill at
solving problems. A more detailed and meaningful measure is desirable both
for research in education and for use by physics instructors. A version of
an assessment instrument has been developed at Minnesota in the form of a
rubric, which evaluates students’ written solutions to physics problems
across multiple scales. In this seminar I will address the instrument
design process and report results from initial tests of validity and
reliability. In addition, seminar attendees will have an opportunity to
use the rubric with sample student problem solutions.

A complete formulation of quantum information theory must simultaneously take into account at least three important concepts or principles, namely: (a) quantum entanglement, (b) quantum coherence versus decoherence (i.e., in the presence of dissipation), and (c) the quantum-classical limit (or quantum-classical interface). We discuss how the mixed coherent states that we have introduced can provide a valuable tool in implementing these ideas.

Understanding QCD is one of the preeminent problems in all of physics. I
would like to venture into the world of high density QCD and explain some of the interesting physics that occurs there. Specifically, I'll give a brief background of high density quark matter and color superconductivity. Then I'll spend some time on a particular phase of this dense quark matter: CFL-K0. From there, I'll explain some of the physical predictions that can be made about the existence of these phases in a most unique spot, the core of a neutron star!

We will continue last week's discussion on the assessment of problem solving skills and processes using a scoring rubric. I will report initial results from tests of reliability and validity, and we will use the instrument to examine several examples of students' written solutions to physics problems.

Newly-commissioned long-baseline interferometers can scrutinize galactic (and extragalactic) objects with nano-radian angular resolution. This incredible resolution allows us a look into the inner accretion disks of young stellar objects (YSOs) in nearby star forming regions. The inner AU of these "protoplanetary" disks hosts a variety of important and fascinating phenomena: it is the site of magnetospheric accretion lifting material off the disk, the disk material here mediates the orbital migration of newly formed "Hot Jupiter" exoplanets, and, of course, terrestrial planet building occurs in the the inner AU. Here, I will give an overview of recent work in this field, results which have directly challenged existing paradigms of the inner accretion disk and the star-disk connection. Soon, we will have the capability to directly image the inner disk using the CHARA interferometer and I will show some exciting new results imaging the surfaces of rapid rotators and interacting binaries.

Ferromagnetic nanoparticles embedded in a semiconductor are being re-considered as prospective materials for semiconductor spintronics. They possess both good compatibility with semiconductor and high Curie temperature, which cannot be obtained by ferromagnetic semiconductor or ferromagnetic metal alone. Understanding of their spin-dependent transport characteristics is indispensable for any future applications.
GaAs:MnAs in which hexagonal (or zinc-blende) ferromagnetic MnAs nanoparticles embedded in a GaAs matrix is a well-known prototype of this kind of material. We show that hexagonal MnAs nanoparticles, when used as a ferromagnetic electrode in semiconductor based MTJ structure, can work even better than hexagonal MnAs thin film; they showed improved TMR ratio, room-temperature operation, oscillatory behaviors of TMR ratio due to quantum size effect / Coulomb Blockade effect, and so on. Very recently, we have observed an unconventionally huge magnetoresistance (MR) effect (up to 100000%) in MTJs with zinc-blende MnAs nanoparticles. Such a huge MR effect can be explained by a combination of Coulomb Blockade effect and large Zeeman splitting in zinc-blend MnAs nanoparticles. A magnetic-field dependent electromotive force emerged from those MTJs (which we call the “spin battery effect”) was also observed. Those phenomena tell us that spin-dependent transport of ferromagnetic nanoparticles embedded in a semiconductor matrix is richer than we thought.

One important aspect of physics instruction is helping
students develop better problem solving expertise. Besides enhancing the content knowledge, problems help students develop different cognitive abilities and skills. My research focuses on ill-structured or multiple-possibility problems. These problems are different from traditional "end of chapter" well-structured problems. They do not have one right answer and thus the student has to examine different possibilities, assumptions and evaluate the outcomes. To solve such problems one has to engage in a cognitive monitoring called epistemic cognition. Physicists routinely use epistemic cognition when they solve problems. I will discuss the results of two studies. Study one is a semi-qualitative study of expert-novice epistemic cognition level comparison based on the analysis of videotapes of experts and novices solving ill-structured problems. Study two is an intervention study investigating the implications of using ill-structured problems in recitations in an algebra-based physics course on students' epistemic cognition and physics content knowledge.

his interactive session will explore two research frameworks that can be
used to guide the integration of technology into physics education. The RAT (Replace, Amplify, Transform) and the TPACK (Technology, Pedagogy, and Content Knowledge) can be used to help instructors at all levels to decide on a myriad of tools. A broad tour of data acquisition, data analysis, communication, visualization/modeling, and concept exploration tools for teaching and learning physics will be explored using these frameworks.

Space science and geoscience are rich in visual representations of systems that are extends across large domains of space and time in 3-D systems. 3-D aspects can be represented by a variety of means, including perspective and color. These visual representations are generally created by subject matter experts who view the representations as self-evident, but novices may not have the same reaction, particularly when the perspective image is of something unfamiliar. Similarly, color scales are often used to represent information (such as temperature, height, time, flux, or other quantities) with the implicit assumption that red is a low value and blue is a high value. But students may not take that color scale as the major visual clue in the representation. In this talk I will review two studies made by our group that investigate student responses to visual representation of information. In one case the focus was on a 2-D representation of 3-D information through perspective drawing. In the other case the focus was on the use of color to represent a third dimension. We find that novices do not necessarily interpret these representations as intended by their creators.

Integrated spintronic biochip platforms are being developed for portable, point-of-care diagnostic applications. The platforms consist of a microfluidic unit where the bioassay takes place, an arraying and detector chip consisting of target arraying current lines and integrated magnetoresistive sensors, and electronic control and readout boards. Probe biomolecules are immobilized by microspotting over sensor sites, and target biomolecules, labeled with magnetic nanoparticles are arrayed over the probe sites (magnetically assisted hybridization). After proper washing, hybridized targets are recognized by the fringe fields created by the magnetic beads, detected by the incorporated magnetoresistive sensors. Detecting geometries will be reviewed, using either out-of-plane or in-plane bead excitation, and dc or ac detection/excitation. Detection limits using spin valve and tunnel junction sensors will be presented, depending ultimately on platform electronic noise, and sensor noise characteristics. Applications to gene expression chips (Cystic Fibrosis gene mutation detection) and imuno-assay chips (anti-body-antigen recognition, e-Coli, Salmonella detection) will be presented. Spintronic biochip are also being integrated into multi -module lab-on-chip platforms including i) biomolecule extraction from biological fluids (magnetophoresis), ii) PCR modules (if required), and iii) the biomolecular recognition module. Alternative spintronic biochip geometries will also be presented ( lateral flow biosensors), where a magnetoresistive reader scans the surface of a porous strip, where labeled target biomolecules bind to immobilized probes. Finally, a brief review of other biomedical applications of magnetoresistive sensors will be given, from hybrid sensors targeted at biomedical imaging, to magnetic tweezers/sensors for DNA translocation monitoring.

A complete description of quantum information theory needs to incorporate simultaneously at least three important concepts or principles, namely: (a) quantum entanglement, (b) quantum coherence versus decoherence (i.e., in the presence of dissipation), and (c) the quantum-classical limit (or quantum-classical interface). We discuss how the concept of quantum phase space can be enlarged to provide just such a unified and consistent description.

his seminar will focus on Science, Technology, Engineering, and Mathematics (STEM) education problem solving through the use of Model-Eliciting Activities. A Model-Eliciting Activity (MEA) is a real-world client-driven problem. The solution of an MEA requires the use of one or more STEM concepts that are unspecified by the problem - students must make new sense of their existing knowledge and understandings to formulate a generalizable model that can be used by the client to solve the given and similar problems. An MEA creates an environment in which skills beyond mathematical abilities are valued because the focus is not on the use of prescribed equations and algorithms but on the use of a broader spectrum of skills required for effective STEM problem-solving. Carefully constructed MEAs can begin to prepare students to communicate and work effectively in teams; to adopt and adapt conceptual tools; to construct, describe, and explain complex systems; and to cope with complex systems. MEAs provide a learning environment that is tailored to a more diverse population than typical STEM course experiences as they allow students with different backgrounds and values to emerge as talented, and that adapting these types of activities to STEM courses has the potential to go beyond "filling the gaps" to "opening doors" to women and underrepresented populations in STEM fields. Through NSF-funded grants, multiple MEAs have been developed and implemented with a nanotechnology theme. This presentation will focus on the content, implementation, and student results of two of these MEAs.

In this talk I present a new method for finding sets of exact isolated solutions for a class of Hamiltonians comprising interacting spins and bosons, of relevance to quantum optics and allied areas. I first demonstrate the simplicity and efficiency of the method by applying it to the one-photon Rabi Hamiltonian. I then also apply it to the two-photon Rabi Hamiltonian which is an obvious extension of the previous case, but where the atomic transitions are induced by the absorption and emission nof two photons rather than one. Such nonlinear optical processes have been of considerable interest, with applications to two-photon lasers and two-photon optical instability.

In this seminar I will present an overview of Faculty Development and Post-secondary teacher training from the 1970s to the present, focusing on Physics Departments, and including Chemistry and Engineering Departments. Also discussed will be how these trends have changed over time and how this information fits with the increasing trend for accountability in higher education.

The mu2e collaboration proposes to search for coherent, neutrinoless conversion of muons into electrons in the field of a nucleus with a sensitivity improvement of a factor of 10,000 over existing limits. Such a lepton flavor-violating reaction probes new physics at a scale unavailable by direct searches at either present or planned high energy colliders. The physics motivation for mu2e will be presented, as well as the design of the muon beamline and spectrometer. A scheme by which the experiment can be mounted in the present Fermilab accelerator complex will be described. Prospects for increased sensitivity using the Project X accelerator that is being proposed by Fermilab will be discussed.

The speaker will present the recent progress and open issues in the
numerical study of QCD thermodynamics, with emphasis on the determination of its phase diagram and on the successes of dimensional reduction.

It is believed that magnetic fields in tenuous plasmas can be amplified by turbulent motions through stretching of field lines. Recently, we have suggested that turbulence could be produced by cascade of the vorticity generated behind cosmological shocks, and that the intergalactic magnetic fields (IGMFs) could be amplified by such turbulence in the large-scale structure (LSS) of the Universe Ryu et al., Science 320 (2008) 909.
Cosmological shocks are induced by gravitational clustering of nonlinear structures and they heat and ionize the intergalactic medium. Using a high-resolution, cosmological N-body/hydrodynamic simulation, we first estimate the spatial and temporal distributions of the vorticity and turbulent kinetic energy density in the LSS. We then estimate the fraction of turbulent energy that is converted to magnetic field energy by employing the results from magnetohydrodynamic simulations of the
turbulence dynamo. Applying a conversion factor to the aforementioned LSS simulation, we estimate that the mean strength of the IGMFs at the present universe could be on the order of microG inside clusters and groups and ~10 nanoG in filaments, whereas it should be much lower in sheetlike structures and voids.

Optics is probably the oldest combination of physical science and technology. It was also the first to permit a laboratory demonstration that quantum weirdness is inevitable in nature. Extremely simple optical concepts can be turned into puzzles and paradoxes, and the talk will describe one or two of them, as well as the development of a new category of interferometers designed to reveal them.

Our Universe is not forever: it is expanding and cooling. Several thousands of millions of years ago the Universe was exceedingly hot and dense, it was very close to smooth, and it was rapidly expanding. Now the Universe is clumpy, with the mass concentrated in and around galaxies of stars, it is cool, except near stars, and it is slowly expanding, though the rate of expansion is speeding up again. I will describe the origins of this concept of cosmic evolution, the discovery of key pieces of evidence that show us that this is what actually happened, and some of the research problems, such as the natures of dark matter and dark energy, which we have left for the next generation.

Antineutrino studies are providing fundamental data for both particle physics and geology. Recent results from antineutrino (geoneutrino) studies at KamLAND are coincident with geochemical models of Th and U in the Earth. KamLAND and Borexino antineutrino detectors are on line, thus uncertainties in counting statistics will be reduced as data are accumulated. The SNO+ antineutrino detector, situated in Sudbury Ontario, the middle of the North American plate, will come on line in 3+ years and will be best suited to yield a precise estimate of
the continental contribution to the Earth's Th & U budget. The proposed Hanohano antineutrino detector is oceanic based, designed to be towed to its location and position on the seafloor and is capable of multi-deployment. This detector would provide a precise estimate of the mantle contribution to the Earth's Th & U budget (~15% uncertainty) following a 1-yr deployment. Much needed constraints from potassium-derived antineutrinos remain elusive, but efforts to overcome technical challenges are being studied.
The distribution of heat producing elements in the Earth drives convection and plate tectonics. Geochemical models posit that of the heat producing elements, ~40% are in the continental crust and the remainder in the mantle. Although models of core formation allow for the incorporation of heat producing elements (including a geo-reactor in the core), the core contribution of radiogenic heating is considered to be negligible. Most parameterized convection models for the Earth require significant amounts of radiogenic heating of the Earth, a factor of two greater than geochemical models predict. The initial KamLAND results challenge these geophysical models and support geochemical models calling for a significant contribution from secular cooling of the mantle.

Nothing has captured the human imagination more than the prospect of life outside our own solar system. We are incredibly fortunate that our generation may for the first time get a peak at other worlds, an opportunity to search for life outside our own neighborhood. NASA is currently engaged in a series of mission studies, one of which is being led from Princeton, for a large space observatory to image extrasolar earthlike planets. Such an observatory could be launched as early as the next decade; it will search for terrestrial planets in the habitable zone of roughly 150 nearby stars and characterize them for the potential to harbor life. It will culminate 20 years of indirect planet finding with the first direct image of an extrasolar Earthlike planet. This talk will discuss the recent history of planet finding methods and two concepts being studied at Princeton for a planet finding space telescope, an internal coronagraph and an external occulter. An internal coronagraph uses specially designed masks in the optical train of the telescope, combined with deformable mirrors and a wavefront control system, to attenuate the light from the star and make the companion planet visible. An external occulter is a large screen (roughly 50 m in diameter) flying far from the telescope (about 72,000 km). The occulter blocks the starlight from entering the telescope while letting the planet light through. I'll describe the technologies behind these two methods and our progress in both mission design and laboratory verification.

There is much current excitement about the interesting new physics and unusual physical properties of carbon nanostructures, particularly carbon nanotubes and graphene. A brief review will be given of the physical underpinnings of carbon nanostructures that were developed over the past 60 years, starting with the electronic structure and physical properties of graphene and graphite, and then moving to graphite intercalation compounds which contained the first carbon nanostructures to be studied experimentally. Liquid carbon studies were precursors to the fullerene family of nanostructures and vapor grown carbon fibers were precursors to carbon nanotubes. Particular emphasis is given to the recent developments on the hot topic of graphene and graphene ribbons focusing on recent advances we have made in studying edges in graphene. Perspectives on future research directions for carbon nanostructures are presented.

Mildred Dresselhaus is an Institute Professor of Electrical Engineering and Physics at MIT. Her research over the years has covered a wide range of topics in Condensed Matter and Materials Physics. She is best known for her work on carbon science and carbon nanostructures. She is also one of the researchers responsible for the resurgence of the Thermoelectrics research field 15 years ago. She co-chaired a DOE Study on "Basic Research Needs for the Hydrogen Economy in 2003 and more recently co-chaired of a National Academy Decadal Study of Condensed Matter and Materials Physics. She served as Director of the DOE Office of Science toward the end of the Clinton Administration and as Chair of the as the Chair of the Governing Board of the American Institute of Physics 2003--2008. Professor Dresselhaus is a member of the National Academy of Sciences, the National Academy of Engineering, and has served as President of the American Physical Society, Treasurer of the National Academy of Sciences, President of the American Association for the Advancement of Science (AAAS), and on numerous advisory committees and councils. Dr. Dresselhaus has received numerous awards, including the US National Medal of Science and 24 honorary doctorates. Her recent awards include the L'Oreal-UNESCO 2007 North American Laureate for Women in Science, and the 2008 recipient of the Oersted Medal for Physics Education from the American Association for Physics Teachers and of the 2008 Buckley Prize for Condensed Matter Physics from the American Physical Society.