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Honors Graduation 2012

Sigma Pi Sigma - first chapter - 2011

Physics Club trip at NASA

A&S Fall Welcome 2011

Jesse Hall

Teacher Academy - Physics First

Life Sciences Bldg.

Research Posters

A&S Fall Welcome 2011

Undergraduate Physics Seminar: building a tower of balloons

Fall on MU campus

Class time

Teacher Academy - Physics First

Physics Bldg.

MU seal on the East wall of the Physics Bldg.

Commencement 2007

Projects for MU Physics Research Experience for Undergraduates in Materials and Modeling

The selected applicants will be matched up with a faculty mentor, keeping in mind their research interests. We have preselected some typical projects keeping these guidelines in mind. Additional information on each faculty member’s research group can be found at http://physics.missouri.edu/faculty.

Faculty Mentor Project description Research
Dr. Shi-Jie Chen
Modeling RNA folding Theoretical
Dr. Shubhra Gangopadhyay
Tunable Pt nanoparticle based single electron memory Experimental
Dr. Suchi Guha
Charge transport in polymer-based transistors Experimental
Dr. Gavin King
Single molecule approaches to membrane proteins Experimental
Dr. Ioan Kosztin
Molecular dynamics: water transport in channel proteins Theoretical
Dr. Aigen Li
Optical and Thermal Properties of Solids in Space Theoretical
Dr. Paul Miceli
X-ray studies of nanostructured metals grown on silicon Experimental
Dr. Peter Pfeifer
Tunable single electron memory Experimental
Dr. Sashi Satpathy
Computational condensed matter physics Theoretical
Dr. Deepak Singh
Nanofabrication of Magnetic Memory Data Storage Device Experimental
Dr. Haskell Taub
Neutron scattering studies of model membranes Experimental
Dr. Carsten Ullrich
Ultrafast optical processes in organic semiconductors Theoretical
Dr. Giovanni Vignale
Spin-orbit interaction at oxide interfaces Theoretical
Dr. Ping Yu
Quantum Entanglement Using Dynamic Holography Experimental
Dr. Xiaoqin Zou
Modeling bio-molecular interactions Theoretical

 

Project Descriptions

Dr. Chen: Modeling RNA folding

Dr. Shi-Jie Chen has extensive experience with physics-based modeling of biomolecular structure and function, especially on the folding of ribonucleic acid (RNA) molecules.  Recently, his research group has made vigorous efforts in the theory development for the prediction of the thermodynamic stability and folding kinetics of RNA tertiary structural formation. Advances in the results of the research are directly correlated to the understanding of gene regulation, early detection of disease, and rational design of therapeutic strategies.  The students would have an excellent opportunity to learn the biological significance of biophysics research. The major theories used in the research are statistical mechanics and electrodynamics.  The research requires both theoretical and computational studies. Through participation in the project, the student will receive rigorous training in both analytical theory development and computational programming.  The research projects involve close interactions with experimental biology labs in the medical school such as Professor Donald Burke’s lab in the Department of Molecular Microbiology and Immunology.  In summary, the combination of the above factors makes Chen’s lab an ideal host for the training of the undergraduate students.

What the undergraduate student intern will do:  The student involved in the REU project will participate in the development of the computational model for RNA folding kinetics, including the computational modeling and test/refinement of the model through comparisons with experimental results. The intern will perform simple analytical derivations and will work with others in the lab to develop a numerical algorithm, by writing computer code and performing numerical calculations using the state-of-the-art University of Missouri Bioinformatics Consortium computer cluster. The student will also participate in the processing of numerical results, presentation of these results at the conferences, and in preparation of publishable illustrations for the resulting papers.

Dr. Gangopadhyay: Tunable Pt nanoparticle based single electron memory

Professor Shubhra Gangopadhyay’s research group has developed a metal nanoparticle deposition technique where nanoparticles are deposited at room temperature using a tilt target sputtering system. With this method, they can control the spherical shaped sub-2 nm size tunable Pt and gold nanoparticles with high densities > 5 × 1012 particles/cm2 and narrow size distributions. The size and density of particles are controlled by varying the process parameters. This deposition technique has been utilized in non-volatile memory devices where each Pt nanoparticle serves one electron storage node due to the small ~1 nm size of the nanoparticle [4]. In addition, they demonstrated unusual current-voltage characteristics in the floating gate memory structure, utilizing 0.8 nm Pt nanoparticles embedded in which Al2O3 dielectric layers. The behavior of Au nanoparticles deposited between two metal electrodes, with less than 50 nm spacing, formed by electron beam lithography (EBL) on Si substrates with 200 nm SiO2 insulating layer is also investigated by her group. Coulomb blockade staircase and single electron tunneling oscillations have been observed at room temperature in these single electron transistor (SET) devices. This project, funded by National Science Foundation, is currently supporting two undergraduate students through NSF REU program. One of the minority REU students Reginald Jeff investigated Pt nanoparticle based GaAs floating gate memory device and published the paper in Applied Physics Letters this year (R. C. Jeff Jr., , M. Yun, B. Ramalingam, B., Lee, V. Misra, G. Triplett, and S. Gangopadhyay, Charge storage characteristics of ultra-small Pt nanoparticle embedded GaAs based non-volatile memory, Applied Physics Letters (in press), 2011.

What the undergraduate intern will do: During the research period, the REU undergraduate student will be trained on the ebeam lithography of metal electrodes (2 weeks), fabrication and electrical characterization of SET device (4 weeks) Finally, the student will investigate the charge transfer characteristics of these devices for chemical sensing (3 weeks). The student is expected to write a paper suitable for publication in a high quality physics journal.

Dr. Guha:  Dynamic charge transport in polymer-based transistors

Prof. Guha’s current research interests are in the area of organic optoelectronics spanning all the way from optical spectroscopy of materials to devices. Her current research group includes four full-time PhD students, two undergraduate students, and a visiting faculty member. Her research utilizes (1) optical spectroscopic techniques such as Raman scattering, photoluminescence/absorption, modulation spectroscopy; (2) organic device fabrication (spincasting, thermal evaporation and modified pulsed laser deposition techniques); (3) electrical characterization techniques, which include current-voltage and capacitance measurements. Her current work, funded by the National Science Foundation, focuses on understanding charge transport mechanisms in organic field-effect transistors (FETs) and organic metal-insulator-semiconductor (MIS) diodes using various characterization techniques such as, current-voltage and capacitance measurements. An additional facet of this work includes vibrational spectroscopy from organic FETs and light-emitting-diodes under applied electric-fields. These studies elucidate the role of conformational changes in the molecules/polymers along with insights into the role of polarons/bipolarons in charge-transport.

What the undergraduate student will do — Typically the field-effect mobility in organic FETs is extracted from a measurement of the current-voltage characteristics made with DC or quasi-DC-measurements. Such measurements do not give any information on the drift mobility and velocity of the charge carriers at shorter time scales (tens of microseconds). The proposed REU project will involve dynamic charge carrier measurements from organic FETs based on both time-domain and frequency-domain characterization of FETs. These measurements will result in an accurate determination of the drift mobilities in organic FETs. The project will further develop a drift-diffusion-based theoretical model to simulate the experimental results in order to gain a deeper insight into electric-field and charge-density dependence of the carrier mobilities. The REU student will be trained both in the fabrication and characterization of organic FETs. The dynamic charge transport measurements will involve setting up a new experimental setup involving a voltage pulse generator and a fast oscilloscope. The student will also be trained in LabView programming for automating some of the experimental steps with the electrical measurements.

Prof. Guha has involved more than 15 undergraduate students in her research since 2000. These students have been supported by several external grants (NSF-REU supplement, Research Corporation, and Petroleum Research Fund). This has resulted in many research presentations at international meetings and peer-reviewed publications coauthored by her undergraduate/high school students.

Dr. King: Precision single molecule approaches to the structure and dynamical properties of membrane proteins

The King lab addresses central questions in membrane biophysics by developing and applying a unique single molecule measurement apparatus, the ultra-stable atomic force microscope (US-AFM). Notwithstanding its many successful applications in biology, AFM performance is directly limited by unwanted mechanical drift between the probe tip and the sample. King’s US-AFM has achieved atomic-scale tip-sample stability over long time periods in ambient operating conditions, representing a 100-fold improvement over prior state-of-the-art [40]. Current projects aim to shed light on central questions in protein secretion and are designed to provide a more detailed understanding of this vital, but ill-understood phenomenon.

What the undergraduate student will do — Several undergraduate projects which are self-contained and achievable in approximately nine weeks of work are outlined. i) Exploring novel sample preparation protocols for functional adhesion of membrane bound proteins to surfaces: To exploit the full power of ultra-stable AFM lateral diffusion within the membrane needs to be suppressed. Experiments with the translocon complex (SecYEG) will utilize an existing library of cystine-tagged SecYEG complexes in conjunction with Au-coated substrates. The successful protocol will tether membrane-bound SecYEG to the substrate to prevent diffusion without denaturing the protein. ii) Data processing and data analysis algorithms for AFM images of membrane proteins: The student will develop and fine-tune particle identification algorithms which yield salient quantities such as volume, surface area, and height of individual features in an image. This analysis is critical to quantitatively assess the distribution of feature sizes, orientation and oligomeric state of the active translocon complex. iii) Tip selection and compatibility: With the US-AFM we have found that different AFM tips yield different optical signals, which alters sensitivity and precision. Here, the student will develop a database of commercial AFM tips’ compatibility with our novel optical stabilization technique. Creating a thorough database will guide our work (as well as others in the field) when selecting tips for specific future applications.

Dr. Kosztin: Molecular dynamics study of water transport through channel proteins

Dr. Kosztin’s group has extensive expertise in the computational and theoretical modeling of molecular and ion transport through channel proteins and artificial nanopores. These processes are inherently multiscale in nature because one needs to follow the dynamics of the transported molecules/ions on an atomic length scale (i.e., a few nanometers) during macroscopic time scales (milliseconds or more). In spite of the spectacular recent advances in massively parallel computing, the use of straightforward molecular dynamics (MD) simulations is not feasible to calculate the permeability of channel proteins. However, by assuming that the transported molecules undergo overdamped Brownian dynamics, this hurdle can be overcome by the following two-step approach: (1) determine the free energy profile U(x) and the underlying (position dependent) diffusion coefficient D(x) of the molecule along the axis of the channel, and (2) solve the appropriate stochastic equation of motion with U(x) and D(x) to calculate the desired physical observables (e.g., flux and channel permeability). This approach has been perfected in Dr. Kosztin’s group and successfully applied to several systems.

What the undergraduate intern will do – The intern will build a periodic system of four hexagonally packed, (6,6) armchair type, single walled carbon nanotubes (SWNT) by employing molecular modeling software VMD. Then, using VMD, pre-equilibrated (~20A thick) water layers will be added on both sides of the SWNTs. Next, the intern will use MD simulations, first to equilibrate the solvated SWNT system at room temperature and pressure, and then to record the diffusive dynamics of water molecules across the SWNTs. All MD simulations will be carried out with the parallel program NAMD. All computer modeling and simulations will be done on a multicore CPU laptop or desktop. The intern will analyze the obtained MD trajectories by: (1) counting the number of water molecules that crosses the SWNTs in both directions, and (2) determining the water distribution function and the corresponding free energy profile U(x). The intern will use these results to calculate the water flux, diffusion coefficient, and mean first passage time through a SWNT. To assist the intern in efficiently performing the above sequence of complex activities, Dr. Kosztin will provide a set of hands-on tutorials. The intern will complete the project by writing a comprehensive report in the style of a research paper.

Dr. Li: Optical and Thermal Properties of Solids in Space

Dr. Aigen Li is a theoretical astrophysicist whose primary research focus is the extinction and infrared emission properties of solids in space (“cosmic dust”). Cosmic dust absorbs and scatters starlight in the ultraviolet and visible wavelength range and re-radiates the absorbed energy in the infrared. Fundamental research to understand how cosmic dust obscures starlight and emits in the infrared is one of the most pressing needs to interpret properly observational data from space telescopes such as Hubble, Spitzer, Herschel, and the future James Webb Space Telescope (JWST).

What the undergraduate student intern will do: The REU student will work closely with Dr. Li to study the optical properties of solids expected to form in the atmospheres of brown dwarfs. Brown dwarfs are star-like objects with insufficient mass to ignite hydrogen fusion in their cores. Over time they cool to temperatures of just a few hundred degrees. The student will calculate the opacities and spectral signatures of these solid species in brown dwarfs. Alternatively, the student could study the optical and thermal properties of nano-diamonds in planet-forming disks. The student will investigate how nano-diamonds absorb stellar photons and get vibrationally excited and then emit in the infrared.

Dr. Miceli: X-ray Studies of Novel Nanostructured Surface Morphologies of Metals Grown on Silicon

Prof. Miceli’s research explores the growth mechanisms of epitaxial films and nanostructures in order to better understand their fundamental properties as well as to utilize these materials in new technological applications. Because his in situ synchrotron x-ray scattering techniques probe both the surface and subsurface regions of the materials, his research has provided unique insight to these problems. His recent work has discovered the incorporation of vacancy nanoclusters during the growth of metallic films as well as revealed the novel coarsening and kinetic behavior of nanoscale metallic crystals that are influenced by quantum-size-effects [43, 44]. Prof. Miceli designed, constructed and operates an extensive ultra-high vacuum facility for in situ synchrotron x-ray scattering studies of nanostructure growth at the Advanced Photon Source, which is located at Argonne National Laboratory. Recently, he constructed a UHV in situ growth system with an x-ray generator at the University of Missouri that can provide preliminary data as well as measurements that are complimentary to the synchrotron studies. This latter facility will be the central tool for the proposed REU project.

What the undergraduate student will do — The REU student will investigate vacancy nanoclusters that incorporate into metallic films during their growth. The subject is important for understanding the fundamental mechanisms of metallic film growth because current theoretical work, based on known growth mechanisms, has failed to predict such vacancy clusters and because conventional surface science experimental techniques are unable to detect the incorporation of subsurface defects. Moreover, the growth of these structures can be manipulated by changing the angle of deposition in order to create novel nanostructured surface morphologies for potential technological applications. However, little is known about the early stages of growth at low coverage [45]. The REU student will work with the PI and senior graduate students to synthesize metallic films on silicon substrates. X-ray reflectivity, measured in situ at the PI’s MU lab, will reveal the metallic porosity and growth morphology as a function of growth conditions. Ex situ atomic force microscopy is also available for complementary information. In the course of the project, the REU students will gain experience with important experimental techniques such as ultra-high vacuum and film growth science as well as x-ray scattering methods.

Dr. Pfeifer: Alternative fuel technology

Dr. Pfeifer leads a research program, the “Alliance for Collaborative Research in Alternative Fuel Technology” (ALL-CRAFT, http://all-craft.missouri.edu/), which, since its inception in 2004 under a same-named NSF-PFI project (Partnerships for Innovation, 2004-07), has involved over 20 senior researchers, 20 Ph.D. students, and 40 undergraduates. The program is a partnership of MU (lead institution), Midwest Research Institute in Kansas City, and other partners (domestic and abroad) to develop low-pressure, high-capacity storage technologies for natural gas (methane) and hydrogen as alternative fuels for advanced transportation. ALL-CRAFT has developed high-surface-area nanoporous carbons, with surface areas over 3000 m2/g—made from waste corncob, a low-cost raw material native to the Midwest (patent pending), and synthetic materials—which adsorb methane at the unprecedented capacity of over 130 g methane/liter carbon (200 times its own volume of natural gas, 110% of the DOE target) at ambient temperature and pressure of 35 bar, and also record amounts of hydrogen. The immediate objective is to replace bulky, cylindrical compressed natural gas tanks in current natural gas vehicles by a lightweight, flat-panel (conformable), low-pressure tank, with storage as adsorbed natural gas, in the floor of next-generation natural-gas vehicles, and similarly for hydrogen vehicles. The program is currently funded by DOE (BES and EERE), DOD (DLA), and the California Energy Commission.

What the undergraduate student will do — A typical project for a summer intern is measurement and analysis of methane storage isotherms (methane uptake as a function of gas pressure) on a series of samples of interest, including determination of binding energies from isotherms, determination of surface areas, porosities, and pore-size distributions of samples (nitrogen adsorption at 77 K), interpretation of results as a function of physical/chemical structure and production conditions of samples, and recommendations for production of improved samples. Students receive on-the-job training in the operation of state-of-the-art adsorption instruments, high- and low-pressure gas handling equipment, cryogenic equipment, sample preparation and characterization, and thermodynamics and statistical mechanics of adsorption and thin fluid films.

Dr. Satpathy: Computational condensed matter physics: dislocation states in semiconductors

Prof. Sashi Satpathy, is an expert in computational condensed matter physics, particularly on the electronic structure theory of solids, including ab initio density functional calculations. His group is involved in the studies of a variety of topics such as two-dimensional electron gas at the oxide interfaces, the RKKY interactions in graphene, Dynamical Jahn-Teller effect in vacancy systems, Kosterlitz-Thouless transition at the oxide interfaces, Skyrmion crystals, etc. Keeping in mind that this will be the first time that the student may be doing research, the objective of the REU project is to introduce to the student the elements of scientific computation, while at the same time applying the methods to a problem of current interest. The project will involve the solution of the defect states bound to the dislocations in semiconductors. There are two reasons why this is interesting. First, electronic properties in semiconductor applications are often controlled by the defect states, which are due to not just the extrinsic defects, but also intrinsic defects such as vacancies, grain boundaries, and dislocations. Second, from a fundamental point of view, these are one-dimensional systems, and defect electrons bound to the dislocations could be a novel realization of the Tomonaga-Luttinger liquid.

What the undergraduate student intern will do: The student will solve the one-particle Schrödinger equation for an electron bound to a model potential describing the dislocation strain field. First, the student will develop a variational wave function and obtain the ground-state energy by minimizing the expectation value of energy. This will be applied to several semiconductors. This in itself could potentially lead to a journal publication. If time permits, the second part of the project would involve an accurate solution of the Schrödinger equation by a numerical integration of the differential equation. The student will learn elementary Quantum Mechanics, computational techniques, as well as some simple semiconductor physics, with a reasonable expectation for a published paper.

Dr. Singh: Nanofabrication of Magnetic Memory Data Storage Device

Dr. Singh is an experimental condensed matter physicist with focus on magnetism and superconductivity. He uses various sample fabrication and measurements techniques to study new materials that are of fundamental importance as well as hold promises for technological applications. One example is the nanofabrication of sub-20 nm ultra-small metal rings arrays. Depending on the selection of the ring material, arrays of ultra-small metal rings can be used to study mesoscopic quantum interference, as evidenced by the Bohm-Aharonov effect, or to create new magnetic memory devices with ultra-high packing density. Magnetic nanorings offer technological advances for potential use in binary data storage due to the two states of clockwise or counterclockwise vortex magnetization. The lack of poles in a ferromagnetic ring leads to a high degree of magnetic stability and small crosstalk with neighboring rings. Historically, ‘ring core’ memory on the micron size scale was one of the earliest forms of magnetic data storage. Today, one design of magnetic random access memory (MRAM) utilizes ring geometry.

What the undergraduate student intern will do: The REU student will work on creating arrays of sub-20 nm ferromagnetic rings using electron-beam lithography, diblock patterning, material deposition and dry etching. For the first three weeks, the student will work closely with Dr. Singh’s research group members and electron microscopes core facility at MU to master various nanofabrication and imaging techniques. Once the student feels confident, he/she will work on this project to create arrays of symmetric and asymmetric ultra-small magnetic rings. The magnetic characterization of samples will be performed using Quantum Design Magnetometer (SQUID).

Dr. Taub:  Neutron scattering studies of model membranes

Professor Haskell Taub’s research group uses a variety of experimental techniques and computer simulations to study the physical properties of organic films as thin as a single molecular layer.  Currently, his interest is focused on the structure, phase transitions, and dynamics of bilayer lipid membranes supported on a solid substrate.  These systems are attractive models for more complex biological membranes that form the outer boundary of living cells.  In order to understand the biological function of living cells, knowledge of the diffusive motion of water over and through these boundary membranes is necessary.

Dr. Taub’s lab primarily uses quasielastic neutron scattering as an experimental technique that allows them to investigate molecular motions, particularly hydrogen atoms, which occur on picosecond to nanosecond time scales.  They use state-of-the-art neutron spectrometers at the Center for Neutron Research at the National Institute of Standards and Technology and at the newly constructed Spallation Neutron Source at Oak Ridge National Laboratory.  Recently, the group’s experiments have demonstrated sufficient sensitivity to observe quasielastic neutron scattering from single bilayer membranes supported on a SiO2-coated silicon wafers such as used in the semiconductor electronics industry.  These  measurements offer promise of revealing how water is bound to the membrane and how the presence of the membrane affects the motion of associated water.  In addition, they expect to follow the diffusive motion of hydrogen atoms within the membrane’s lipid molecules.

What the undergraduate intern will do: The undergraduate intern will participate in neutron reflectivity measurements at MURR and assist in the analysis of the membrane reflectivity measurements.  Undergraduate students previously engaging in research in Taub’s lab have demonstrated that their study in introductory courses of interference effects with light scattered from thin films provides an adequate foundation for a conceptual understanding of a neutron reflectivity measurement. The project also reinforces their introduction to modern physics by giving them a first-hand experience with the wave-like properties of neutrons without their needing a detailed understanding of crystal structures and reciprocal space.  The students have had little difficulty learning to manipulate the software available for fitting the reflectivity curves and are able to develop some independence in their modeling of them.

Dr.Ullrich: Ultrafast optical processes in organic semiconductors

Prof. Ullrich has his main research interests in the theoretical and computational description of excitation processes and optical properties of a variety of materials, mainly bulk and nanostructured insulators and semiconductors, organic molecules, and polymers. The common theme is that these processes are described using methodologies of time-dependent density-functional theory (TDDFT). The PI has extensive experience in applying the TDDFT methods to semiconductor nanostructures in linear response and real-time [5], studied spin-dependent collective excitations and transport [6], and calculated excitonic binding energies in bulk semiconductors[7]. TDDFT is a theory that allows one to describe the electron dynamics in interacting many-electron systems in principle exactly, but without the computational effort of wave-function methods. It has become very widely used in computational chemistry to calculate molecular excitation energies, and is gaining more and more interest for applications in solid-state physics and materials science. Ullrich has been consistently supported by federal research grants (NSF, DOE) over the past years. He has so far been working with two graduate students, and has also supervised three undergraduate students in summer research projects. These projects mainly involved computer code development and running various codes.

What the undergraduate intern will do — REU students who will be working with Prof. Ullrich will get the opportunity to participate in computational studies of ultrafast optical processes in organic semiconductors. At the beginning they will receive the necessary training, including some theoretical background on TDDFT and other approaches for electronic structure calculation. The students will then receive tutorials on the use of available computer codes on the PI’s 32-CPU computer cluster. The main code, “octopus”, allows the real-time simulation of optical excitations of molecules and solids by solving the time-dependent Kohn-Sham equations on a grid. Students will, in particular, study optical excitations in materials of interest for photovoltaics applications such as organic chain molecules and polymers. They will learn how to produce numerical results, analyze, and visualize them. The goal is to learn about mechanisms of exciton creation, migration, and charge separation at molecular interfaces. A better understanding of ultrafast exciton dynamics in these materials is crucial for the development of new generations of photovoltaics devices.

Dr. Vignale: Spin-orbit interaction at oxide interfaces

Professor Vignale has extensive experience as a theorist of electronic properties of metals and semiconductors.  In recent years he has worked on the new problems posed by consideration of spin-orbit interaction in spin-dependent transport phenomena (e.g. the Spin Hall Effect) and their interplay with traditional many-body effects (an example of this interplay is the recently predicted “Spin Hall drag”). The objective of the present proposal is to provide research experience for an undergraduate in a rapidly developing field of condensed matter physics, namely the study of oxide interfaces, where spin-orbit interactions are expected to play a large role, which, however, has not yet been fully elucidated. Recent experimental and theoretical investigations [11] indicate that in oxide heterostructures with a polar discontinuity, a quasi-two-dimensional electron gas may form at the interface between two insulating oxides [12].

What the undergraduate intern will do: In this project, the participant will be guided to introduce spin-orbit interactions in the framework of the triangular potential well model of the oxide interface.  The project will consist of two parts.  In the first part, the student will solve numerically the Schrödinger equations of the triangular well in the presence of spin-orbit interaction, and establish the interesting dependence of the wave function on the momentum of the electrons in the plane. Knowledge of this dependence will enable the student to determine the effect of spin-orbit interaction on the effective mass and the mobility of the electrons at the interface.  Next, depending on interest and motivation, the student will be asked to consider the effect of driving an electric current in the plane of the interface.  An electric current in combination with spin-orbit interaction generates a torque, which may change the orientation of the electron spin – an effect of great importance in magneto-electronics.  The student will calculate the rate of spin flip by solving the equation of motion for the spin in the triangular potential well.

The PI will closely supervise the progress of the student, and offer a tutorial introduction to the theory of spin-orbit effects in solids.  This, combined with the experience gained by solving the Schrödinger equation in the quantum well, will make for a good introduction to a very active field of research.  It is expected that the results of the student’s work will lead to at least one significant publication in a journal such as Physical Review B.

Dr. Yu: Quantum Entanglement Using Dynamic Holography

Dr. Ping Yu is a physicist whose research combines semiconductor optics, laser physics and biomedical optical imaging. He has spent his career exploring basic physical processes in optics and optical materials, and applying his acquired knowledge to the development of novel materials, devices, and biomedical imaging systems. The research contributions for which Dr. Ping Yu is best known are: (1) his pioneering work on room temperature stimulated emission, including the lasing and gain mechanism of zinc oxide epitaxial thin films and microstructures; (2) his contribution to understanding optical polarization and electronic states of vertically coupled semiconductor quantum dots; and (3) his innovation in holographic optical coherence imaging and fluorescence mediated tomographic imaging. The biomedical imaging techniques that he is working with have shown great potential for pre-clinical and clinical imaging applications. He is currently developing techniques for holographic optical coherence imaging. Holographic optical coherence imaging provides high-speed direct images without computed reconstructions and is depth-resolved, making it possible to fly through scattering tissue as a succession of optical sections. This project has been funded by the National Science Foundation.

What the undergraduate intern will do: The REU student will be involved in a project to develop a novel quantum entanglement technique using quantum entangled photon states and dynamic holography, and use the developed quantum system to investigate the quantum nature of metamaterials. Metamaterials are artificially structured materials with subwavelength meta-atoms designed to realize extraordinary electromagnetic properties that does not exist in naturally occurring materials. The student will develop an experimental holographic quantum system based on quantum coincident measurements, and metamaterials with exotic optical properties will be designed and characterized.

Dr. Zou:  Modeling bio-macromolecular interactions based on physics principles

Professor Xiaoqin Zou has more than fifteen years of experience with computer modeling of biomacromolecules such as proteins and their interactions. She is particularly interested in development of novel computational and theoretical methods for predicting protein-small molecule (referred to as ligand) interactions and protein-protein interactions using physical principles. Her team was ranked among top three teams that have the best performance in predicting protein-protein interactions by 4th international CAPRI competition. She also applies her physical methods to rational drug design. She closely collaborates with experimentalists to understand biophysical phenomena of disease-associated proteins (including ion channels). She is currently funded by NSF and NIH. She is enthusiastic in mentoring undergraduate research, particularly woman and minority students.

What the undergraduate intern will do: In this project, the participant will be guided closely to perform silico screening of drug candidates against a potassium channel associated with cardiovascular diseases. First, the REU intern will learn basic knowledge of biomolecules, understand physical forces underlying protein interactions, and learn a variety of useful software tools for biomolecular modeling and graphic display. Then, the intern will use the physical methods that have been developed in Professor Zou’s lab to predict the binding tightness of each organic compound in a huge database of molecules against the atomic, three-dimensional structure of a potassium channel. The top 50 compounds that are predicted to bind tightly to the channel will be purchased and assayed by Professor Zou’s experimental collaborator. The experimental results will be used to further optimize the potency of the compounds by physical methods. The compounds that exhibit potent binding activities would have the potential to become (1) useful probes to understand the functions of the channels, and (2) agents for therapeutic interventions of cardiovascular diseases such as long Q-T syndromes. Through the project, the intern will not only learn how to do molecular modeling, but also learn how to interact with experimentalists as a theorist, how to extract experimental information and based on which how to improve theory and provide insightful guidance to experiments. One publication is expected from the project.