Research Projects

Below are examples of projects chosen from the various fields represented.

High Energy and Nuclear Physics

Potential mentors: [[makordosky,Michael Kordosky]], Bob Mckeown, [[jknels,Jeffrey Nelson]], [[plvahle,Patricia Vahle]], [[physics|griff,Keith Griffioen]], [[tdaver,Todd Averett]], Charles Perdrisat


Neutrino-oscillations (with the MINOS, NOvA and Daya Bay experiments), neutrino-nucleus scattering experiments (with the MINERvA experiment), and a test-beam experiment for detector calibration are being carried out at Fermilab, the Soudan Underground Laboratory, and China. The neutrino group maintains detector prototyping laboratories equipped with state-of-the-art test equipment for testing particle detector with radioactive sources and cosmic rays, a high-bay assembly laboratory for large detector development, and a high-performance computing cluster for data analysis and simulations. Projects include design optimization, assembly, testing, and calibration of experiments and analysis projects using the collected data.
Contacts: [[makordosky,Michael Kordosky]], [[jknels,Jeffrey Nelson]], [[plvahle,Patricia Vahle]]

The Daya Bay Reactor Neutrino Experiment in China:

Neutrino mixing angle θ13 is the least understood one in the neutrino mixing matrix. The Daya Bay experiment has the highest sensitivity in the value of sin22θ13 among the current generation reactor neutrino experiments. The Daya Bay experiment is located in Southern China, on a nuclear power plant campus. The Daya Bay group is currently building the last two of the eight detectors and analysing the data taken by the first two near site detectors. Projects on Daya Bay include various data analysis topics, including nuclear reactor antineutrino flux calculation, detector monitoring data analysis and physics data analysis.
Contacts: B. McKeown, [[w|wswang,Wei Wang]]

Spin-dependent electron scattering

Electron scattering on polarized $^3$He is carried out at Jefferson Lab. In support of the research, a fully equipped polarized target facility capable of producing and characterizing target cells is maintained at William and Mary. Projects include development of NMR and EPR systems for target polarimetry, investigating novel cell technologies and analysis of cell data. The research projects can also involve the Jefferson Lab polarized $^3$He target and participation in currently running nuclear physics experiments.
Contacts: Keith Griffioen, [[tdaver,Todd Averett]], Charles Perdrisat

Parity-violating electron scattering

At Jefferson Lab several electron scattering experiments are underway or in development that use electroweak interference to search for physics beyond the Standard Model and to study the structure of nucleons. Detectors for these experiments are prototyped, constructed and tested at William & Mary. Projects include development and testing of particle detectors and their associated electronics, participation in data-taking and data-analysis for running experiments at Jefferson Lab, and computer simulation and software development for future experiments.
Contacts: David Armstrong, [[wdeconinck,Wouter Deconinck]]

Condensed Matter Physics

Potential mentors: [[physics|gina,Gina Hoatson]], [[ralukaszew,Ale Lukaszew]], [[w|luepke,Gunter Luepke]], Ronald Outlaw, [[mumtaz,Mumtaz Qazilbash]].


Nuclear magnetic resonance at W\&M is used to investigate local order and molecular motion and correlate these with the macroscopic physical properties of piezoelectric and ferroelectric materials, inclusion compounds, and polymers. Experimentally, students would use a homebuilt NMR spectrometer designed for a 7 Tesla superconducting magnet. Students could take part in the use of the 17 T facility.
Contact: [[physics|gina,Gina Hoatson]]

Magnetic Multilayers

The group is exploring the deposition and characterization of thin films and multilayers of fundamental interest as well as being important in applications. Magnetic thin films and nanostructures are of great interest for the study of fundamental issues in magnetism as well as their application in computer technology such as spin-torque memory. Other studies include superconducting layers for RF superconducting cavities used in LINACs and the study of the optical properties in complex oxide thin films. Examples of projects include the study of the effects of the substrate on physical properties of thin films. A wide range of experimental techniques would be used, including vacuum thin film deposition, magnetic measurements and ultrafast laser spectroscopy. Contact: [[ralukaszew,Ale Lukaszew]]

Laser Interactions with Solids

The group has projects on the study of local vibrational modes of hydrogen in semiconductors. The aim of this experimental research program is to elucidate the microscopic dynamics of local vibrations of hydrogen-decorated defect and impurity complexes in crystalline semiconductors. Hydrogen is one of the most prominent impurities in semiconductors and has beneficial passivating characteristics.

The population lifetime and the dephasing time of the first excited vibrational level of the hydrogen impurities will be determined using transient bleaching and photon-echo measurements. The time-resolved nonlinear-optical studies will be carried out with the short-pulse high-power tunable-infrared radiation of the Free-Electron Laser at Jefferson Lab. Contacts: [[luepke,Gunter Luepke]]

Infrared and optical properties of inhomogeneous media

Students will study the infrared and optical response of inhomogeneous systems composed of metal particles in an insulating matrix. The optical constants of each of the constituents will be measured using ellipsometry, transmission and reflectance. Furthermore, the macroscopic optical response of the inhomogeneous composites will be measured to determine the precise quantitative validity of various eff?ective medium theories. Connection will be made to the more complex, unconventional correlated electron materials that are known to be inhomogeneous on nanometer length scales. Correlated electron materials of interest include the oxides of vanadium, magneto-resistive manganites, and copper-based and iron-based high temperature superconductors.
Contact: [[mumtaz,Mumtaz Qazilbash]]

Applications of graphene double-layer capacitors for energy storage

Students will work on thin film electrical double layer capacitors (sometimes referred to as ultracapacitors or supercapacitors).  The material is basically vertically oriented graphene nanosheet arrays that are used for energy storage (e.g., solar cells, wind mills, tidal generators) and high power distribution (e.g., hybrid automobiles, buses). The military would use them for lasers, rail guns and electronics where mass and volume are substantially reduced for the soldier. Films are created using RF PECVD and characterized for microstructure by SEM, XRD, surface analysis (AES, XPS, TDS, NEXAFS) and Raman spectroscopy. The capacitance and frequency response (electro impedance spectroscopy) would be evaluated by our collaborators from JME Capacitor and Case Western Reserve University. Contact: [[raoutl,Ronald Outlaw]]

Atomic, Molecular and Optical Physics

Potential mentors: [[w|saubin,Seth Aubin]], [[physics|inovikova,Irina Novikova]], and [[w|eemikh,Eugeniy Mikhailov]]

Optical gyroscopes enhanced by a fast-light atomic medium 

The goal of this project is to evaluate possible enhancement of an optical gyroscope performance by manipulating the dispersion of an atomic ensemble, placed inside the gyroscope cavity. We investigate a new interaction schemes that allow controllable modifications of the propagation of a light field through atoms from slowing it down to a crawl to making it propagate with superluminal (above c) group velocity. The research project will involve experimental analysis of various regimes for probe pulse propagation under a wide variety of experimental conditions, with the goal to identify regimes for lossless propagation with large superluminal group velocity for gyroscope applications.
Contacts: [[physics|inovikova,Irina Novikova]] and [[w|eemikh,Eugeniy Mikhailov]]

Atom-based vector magnetometer 

This project will be focused on development of new methods for magnetic field detection based on coherent narrow resonances using a current-modulated diode laser. Small modulations in modulation frequency or magnetic field orientation strongly affect the optical transmission of resonant atomic vapor, enabling accurate measurements of the magnetic field characteristics. The particular goal of this project is 3D magnetic field imaging, most likely using two different orientations of a laser beam.
Contacts: [[physics|inovikova,Irina Novikova]] and [[w|eemikh,Eugeniy Mikhailov]]

Squeezed vacuum generation 

This project will introduce students to optical fields with non-classical statistics, in particular to squeezed vacuum states: a vacuum state with reduced quantum fluctuations in phase at the expense of larger fluctuations in amplitude or vice versa. The students will work on generation of such squeezed vacuum states in Rb vapor cells, on assembly and testing of a more efficient detection configuration, and on the development of methods for generation and analysis of a pulsed squeezed vacuum field with predetermined temporal pulse shape.
Contacts: [[physics|inovikova,Irina Novikova]] and [[w|eemikh,Eugeniy Mikhailov]]

Whispering gallery modes disk resonators for ultrasensitive temperature detectors 

This project will introduce students to a novel resonator geometry, in which light travels along the rim of a polished crystal disc experiencing constant total internal reflection – a so called whispering gallery mode resonator. A student will be able to cut and polish a disk resonator with extremely high quality and finesse. Such a resonator can be used as a basis for an extremely sensitive thermometer.
Contacts: [[physics|inovikova,Irina Novikova]] and [[w|eemikh,Eugeniy Mikhailov]]

Ultracold molecule production

This project will work on the production of ultracold, weakly bound molecular dimers from ultracold atoms by means of photo-association and magnetic Feshbach resonances. The suitability of such molecules for magnetometry will also be explored.
Contact: [[w|saubin,Seth Aubin]]

Ultrafast frequency comb

This project will work on converting an ultrafast femtosecond laser into an optical frequency comb. The comb will be used to measure and lock large frequency differences between spectroscopy lasers.
Contact: [[w|saubin,Seth Aubin]] 

FPGA-based high-speed laser offset lock

This project will offset lock a laser to a master laser. The offset lock will use an FPGA chip, direct digital synthesis (DDS), and a microprocessor to lock the laser so that it can be scanned and jumped at high speeds over a range of ± 7 GHz. This locking technique will allow us to probe many different atomic transitions over a short time and at high magnetic fields. If the lock is sufficiently good, then it can be used for Raman transitions and 4-wave mixing in gases of ultracold atoms.
Contact: [[w|saubin,Seth Aubin]]

High stability, agile RF source

This project will develop a high stability, agile RF source based on a direct digital synthesis (DDS) chip. The source will be used for RF manipulation of the ultracold atoms for applications including RF evaporation to nanoKelvin temperatures, atomic clocks, and magnetometry.
Contacts: [[w|saubin,Seth Aubin]]

High resolution imaging of ultracold atoms

Most measurements of ultra-cold atom properties such as temperature and density absorption images of the atomic clouds, and so their accuracy is determined by the quality of the imaging system. The project will design, construct, and test a high resolution CCD imaging system for precision optical measurements of ultra-cold atoms.
Contact: [[w|saubin,Seth Aubin]]

Atom chip construction

The objective of this project is to construct a multilayer atom chip by bonding ultrathin wires to a substrate. This "homemade" atom chip can then be used for micro-magnetic trapping and RF evaporation of ultracold atoms. The addition of multiple layers to the atom chip permits the integration of RF and microwave transmission lines for further manipulation of the internal and external atomic states.
Contact: [[w|saubin,Seth Aubin]]


Potential mentors: Carl Carlson[, [[w|cdcaro,Christopher Carone]], [[physics|erlich,Joshua Erlich]] (particle physics); [[w|mtsher,Marc Sher]] (Particle/Astrophysics); [[w|ertrac,Gene Tracy]](Non-linear dynamics); [[w|jbdelo,John Delos]] (Atomic and Molecular); [[w|erossi,Enrico Rossi]], [[w|hxkrak,Henry Krakauer]], and [[w|shiwei, Shiwei Zhang]] (Condensed Matter Physics).

Particle Physics (unavailable until further notice)

Recent astrophysical data have been applied to particle physics questions such as the nature of the mysterious dark matter and dark energy. REU students have combined various data such as the cosmic microwave background and Type Ia supernova probes of the expansion history of the universe. Students can continue this research by performing global fits including recent cosmological data to constrain cosmological parameters.

Another area in which REU students have had an impact is in models of strongly interacting physics motivated by the AdS/CFT correspondence in string theory. Many observables can be calculated in these models by solving equations of motion for fields in extra-dimensional spacetime. Numerical solutions can be found using Mathematica, allowing the prediction of observables. Future projects include an analysis of modifications to existing models in an attempt to improve their accuracy, and, e.g., can also address the phase diagram of quantum chromodynamics. The underlying physics in these projects is complicated for most undergraduates, but the technical requirements are minimal, requiring only an understanding of Lagrangian mechanics and differential equations. A previous William & Mary REU project along these lines has led to a recent publication. Contacts: [[cecarl,Carl Carlson]], [[cdcaro,Christopher Carone]], [[jxerli,Joshua Erlich]] and [[mtsher,Marc Sher]]

Condensed Matter Theory

Building on top of the JAVA program: Diffusion Quantum Monte Carlo, A Java Based Simulation and Visualization Program a student could implement importance sampling and study population dynamics.

A student could make a similar pedagogical tool for a new method developed in our group called auxiliary-field quantum Monte Carlo. A Matlab program has been written for this method. Implementation of visualization of this calculation would be very useful.

Dirac materials are a new class of materials that have recently been realized experimentally. Examples of Dirac materials are graphene and 3D topological insulators. In a Dirac material the electrons behave as massless Dirac fermions. In the presence of disorder to achieve experimentally relevant results it is necessary to consider several disorder realizations. This can be done efficiently by solving several copies of the physical problem with different disorder realizations in parallel on a supercomputer. The parallelization and solution of the mathematical equations describing the physics of Dirac materials in the presence of disorder, and the visualization of the results, do not require an advanced knowledge of the underlying theoretical models and would be very helpful for our understanding of the interplay of interactions and disorder in these materials. Contacts: [[erossi,Enrico Rossi]], [[hxkrak,Henry Krakauer]], [[swzhan,Shiwei Zhang]]

Atomic and Molecular Theory

Transport and Control at the Quantum-Classical Boundary

The construction of quantum wave-functions from classical trajectories provides a unique depth of insight. The breakup of excited states of atoms and molecules can described using chaotic transport, and a mathematical construct called a homoclinic tangle. Currently we are examining transport in ultracold gases, which as a function of temperature goes from the extreme quantum regime to the semiclassical regime. We are now predicting and will interpret the results from experiments by S. Aubin. This topic was initiated in undergraduate research projects, and four undergraduates have contributed to and are co-authors of papers we have already published on this subject. Contact: [[jbdelo,John Delos]]

Interdisciplinary topics

Potential mentors: [[w|jbdelo,John Delos]], [[w|wecook,Bill Cooke]], [[w|hinders,Mark Hinders]], [[w|ertrac,Gene Tracy]], and R. Wincheski

Non-Destructive Evaluation

Nondestructive Evaluation (NDE) is an interdisciplinary field of study which is concerned with the development of analysis techniques and measurement technologies for the quantitative characterization of materials, tissues and structures by noninvasive means. Ultrasonic, radiographic, thermographic, electromagnetic, and optical methods are employed to probe interior microstructure and characterize subsurface features. Applications are in non-invasive medical diagnosis and on-line manufacturing process control, as well as the traditional NDE areas of flaw detection and materials characterization. There are many topics exploring expanding the application of these techniques. The student would learn a technique and aid in its development.
Contacts: [[w|hinders,Mark Hinders]]

Biofuel Development/Environmental Remediation

Algal-based biofuel holds great promise for being a renewable energy source. However, many current approaches produce biofuel while severely taxing the environment by using water, energy, fertilizer, and producing excessive Greeenhouse gas. Our approach, growing wild algae in its natural environment, solves all these problems and it can clean up the Chesapeake Bay as an added benefit. This project is still in its earliest stages, so we need aspiring physicists to develop new technology, to model the planned algae farms, and to help with the experiments on the picturesque York River , near the Virginia Institute of Marine Science.
Contact: [[w|wecook,Bill Cooke]]

Medical Physics

Development is underway of a continuous, noninvasive, purely electronic monitoring systems to give warning of infectious disease in infants in neonatal intensive care u, and to monitor for apnea in such infants. Data from neonates have been collected and now three types of quantitative analyses of this new data set are needed: (1) statistical analyses, to give precise numbers representing risk of infectious disease or impending apnea events; (2) pattern recognitions, to identify apnea events in the chest impedance signal; (3) systems modeling of the coupling between heart and respiration, to provide at least partial explanations of normal and abnormal behaviors.
Contacts: [[w|jbdelo,John Delos]]

Advanced Material Characterization Research at NASA Langley Research Center

Potential research projects exist in the characterization of advanced materials for aerospace applications.  In one area, the development of a sensory alloy for localization of high strain fields in airframe structures is under development. During the summer the student would assist in the characterization of the prototype material using a novel sensor developed to measure the magnetic and electrical properties of the material at sub-millimeter length scales.   The student will assist/be responsible for data acquisition during controlled fatigue crack growth experiments, data processing and analysis.

A second potential project area involves the characterization of carbon nanotube based materials for structural applications.  NASA Langley Research Center is leading an effort to develop structural nanocomposites based on commercially produced carbon nanotube yarns and sheets.  While the materials have been applied for electrical applications, the structural performance of the materials currently lag behind that of state of the art carbon fiber composites.  This research effort is designed to develop methods to increase the strength of the nanotube based materials through alignment of individual carbon nanotubes, densification of nanotube sheets and yarns, and cross-linking of individual and bundled tubes.  The student will participate in the optimization process and measurement of optical, electrical, and/or ultrasonic properties of the materials at various stages in processing. Contacts: Russell A. Wincheski and Matthew Douglas Rogge

Physics Education

Students interested in physics education will have a chance to develop experiments for undergraduate or high school projects. An example experiment is using a torsion pendulum technique for measurements of anisotropic magnetization or applications of the Arduino microprocessor. Contact: Jack Kossler