Physics Internships

This summer I helped work on two papers that arose during the 2022 Research Experience for Undergraduates in Algebra and Discrete Mathematics at Auburn University. The papers were in the areas of Graph Theory and Number Theory. This research was supported by NSF (DMS) grant no. 1950563. 

As a summer research scholar at CMMS at Troy University, my main goal was to study the physical and chemical properties of High/Low density Polyethylene when it combines with various natural polymers like Lignin, Cornstarch, in the presence of Oxidized Polyethylene at different volume compositions. 

In a series of controlled experiments at the Magnetized Dusty Plasma Experiment (MDPX) at Auburn University we have previously observed the formation of filamentary structures in capacitively-coupled, rf generated plasmas at high magnetic field (B ≥0.5 T), under a variety of power, pressure, and applied magnetic field conditions. These elongated plasma filaments, when viewed from the side, appear as bright vertical columns aligned parallel to the magnetic field. These structures can either be stationary or mobile, depending on the experimental conditions. In a certain parameter range of neutral pressure, power and magnetic field, a regime of individual filaments with rotating spiral arms has been identified by visible imaging from the top of the machine. These are probably due to instabilities of the original vertical plasma column, producing such azimuthal spirals. More high resolution imaging can shed light on the nature of these instabilities. In this project, we will work on detailed camera data analysis to identify the filamentary structures, investigate the nature of the spiral arms, understand spatiotemporal patterns and finally use statistical methods to characterize these filamentary structures as a function of the magnetic field and neutral gas pressure. We shall also learn about plasma instabilities.

 

 

 

Details coming soon.

This summer I am working with Vanderbilt's Physics Department in the research area of wound healing.  My specific project is "Measuring Spatiotemporal Characteristics of Calcium Flares around Laser-Induced Epithelial Wounds" under the guidance of Aaron Stevens and Dr. Shane Hutson. This project studies the influx of calcium into wounded epithelial cells, which is the first observed signal upon wounding. Calcium oscillates around wounds to signal nearby cells in order to begin the healing process, and this occurs in many stages. The last stage of these calcium waves after wounding is called flaring, which is the focus of my project because its purpose is not known. To learn more about flaring, a code was previously developed in Mathematica to measure various spatiotemporal characteristics of calcium flares around laser-induced epithelial wounds in fruit fly pupae. My project utilizes and expands upon this code to measure other flare characteristics important in uncovering the purpose of the flares. This analysis will be used to help build a computational model and understand more about the wound healing process.

I was chosen for the 2020 NNCI (National Nanotechnology Coordinated Infrastructure) iREU program in Japan this summer. I will be working with Dr. Hidenori Noguchi at NIMS (National Institute for Materials Science) in Tsukuba, Japan, which is just north of Tokyo. My project will be on real time monitoring in situ of energy conversion processes at solid/liquid interfaces. I will be working with many different microscopes such as an Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) to understand many processes key to energy conversion. That information is essential for the development of energy conversion devices with high efficiency and durability. Not only will I get to learn next level research, but I will get to experience Japan and the culture. This internship pays housing, travel, and gives an additional stipend. I am very excited and grateful to have been chosen for this opportunity! Who knew a small town girl would end up being able to go to one of the biggest cities in the world for research?

 Cancelled due to COVID-19.

Rachid Bowles

Summer research - IRES 2019: This summer I will be doing research at the Technical University of Liberec in Liberec, Czech Republic. My research project is about nanofibers and the process behind electrospinning them, specifically using AC (alternating current). I currently have two projects that I will be working on. In my personal project I will be making samples of a polymer, PVA (Polyvinyl alcohol), and water. With those samples I will do viscosity and conductivity testing and spin them using the AC spinning method so; I can take images of the collected fibrous sheets, determine their morphologies, and measure their mechanical properties. I will also be collaborating with a graduate student from UAB to work towards understanding the physics behind AC electrospinning.

 

My project this summer involves a study of the Strain Localization during Slow Strain Rate Testing of Sensitized Al-Mg Alloys. In simpler words, I perform tensile tests on an aluminum alloy and observe its condition in an SEM (Scanning Electron Microscope) to understand the strain localization behavior of the metal. The purpose of this research is to make aluminum stronger, while maintaining it's other desired features (light weight, low cost of production, etc.). Here is a picture of me working on a SEM in the Marcus Inorganic Cleanroom.

 

This summer I am working at CentralSupélec in Paris, France. My goal is to study the ultrafast  optical response of gold nanoparticles by broadband laser spectroscopy. Light incident on a metal nanoparticle causes the conduction electrons to oscillate. Excitation of the nanoparticles at a resonant frequency results in the creation of a strong electromagnetic field. This phenomenon is known as localized surface plasmon resonance (LSPR). Thanks to the properties of LSPR, one can quickly and efficiently inject energy into the nanoparticle system using ultrashort pulses of light. Ultimately, I hope to excite a system of gold nanoparticles to overheat the water within cancer cells and kill them.

Aashish Kafle is at the University of Virginia this summer: We are setting up a lab for quantum simulation of bosonic and fermionic quantum many-body systems with ultracold atoms in optical lattices using recently developed techniques of quantum gas microscopy. The well-developed methods of laser cooling and atom trapping are at the heart of the experimental system and that is what I have been helping in currently. These methods allow cooling atoms into the quantum regime at a few billionths of a degree above absolute zero, where the particle statistics is dominating. By loading ultracold atoms into optical lattices very clean realizations of a wide variety of condensed matter models are obtained. The fresh and new view on condensed matter model systems provided by ultracold atoms can help to identify the essence of the physics in these systems guiding us to the understanding of real-world quantum materials with competing quantum effects.

Pawan Khanal at the Department of Physics and Biophysics, University of San Diego.

Project: Triggered disassembly and reassembly of actin networks induce rigidity phase transitions. Non-equilibrium soft materials, such as networks of actin proteins, have been intensely investigated over the past decade due to their promise for designing smart materials and understanding cell mechanics. However, current methods are unable to measure the time-dependent mechanics of such systems or map mechanics to the corresponding dynamic macromolecular properties. Here, we present an experimental approach that combines time-resolved optical tweezers microrheology with diffusion-controlled microfluidics (I do the microfluidics part of this project) to measure the time-evolution of microscale mechanical properties of dynamic systems during triggered activity. We use these methods to measure the viscoelastic moduli of entangled and crosslinked actin networks during chemically-triggered depolymerization and re-polymerization of actin filaments.  We develop toy mathematical models that couple the time-evolution of filament lengths with rigidity percolation theory to shed light onto the molecular mechanisms underlying the observed mechanical transitions. The models suggest that these two distinct behaviors arise from phase transitions between a rigidly percolated network and a non-rigid regime. Our approach and collective results can inform the general principles underlying the mechanics of a large class of dynamic, non-equilibrium systems and materials of current interest. 

I spent this past summer working at the National High Magnetic Field Lab in a materials testing lab with my mentor Robert Walsh. Specifically, I worked on the material properties and characterization of an epoxy that was invented at the lab for use in vacuum impregnating large superconducting magnets. I did extensive testing on the epoxy at cryogenic temperatures and submitted a report that will later be published. A summary of my work can be found online at nationalmaglab.org on the REU class of 2018 page.

I spent my summer as a research student at Auburn university where I worked on computational magnetospheric physics with Dr. J. D. Perez. My work included studying the interaction of solar storms with the earth’s magnetosphere through the analysis of data obtained from NASA’s TWINS (Two Wide-Angle Imaging Neutral-Atom Spectrometers) mission. All the work I did is submitted to the TWINS geomagnetic Storm Catalog and can be accessed here.

              

My summer project was to analyze photogrammetry data of the Baryon Mapping Experiment radio telescope. The telescope has been built to gather data for spectral lines emitted from 21 cm neutral hydrogen for the purposes of intensity mapping. Since the universe was primarily comprised of neutral hydrogen during the Dark Ages, looking at these wavelengths at high redshifts will give a good map of the large scale structure of the universe during that period. I analyzed pictures of the telescope's dish surface using a photo-processing software. This involved writing code to find position of targets laid on the parabolic dish surface and producing a "best-fit" curve. This would help to confirm the orientation of the telescope; namely the translation, rotation, and focal length. Click here for more information.

Her project focused on the source of electrical resistance in tin oxide single crystals. Tin oxide crystals are being studied for use in transparent electronic components, and the aim of the project was to find the source of resistance and hopefully reverse its effects on the crystals. Electron Paramagnetic Resonance (EPR) and X-ray Photoelectron Spectroscopy (XPS) were two of the main methods used to test for the source of resistance. Victoria earned second place in the poster presentation competition for the Physical and Applied Sciences division.

Elastin-like polypeptides (ELPs) are a class of biopolymers that undergo a reversible phase transition occurring at a transition temperature. Recently, six-armed star polymers have been synthesized with arms composed of ELPs. My goal this summer was to characterize the solution properties of two six-armed ELP star polymers, the G10 and G19. Above their transition temperatures, these proteins aggregate into nanoparticles of different sizes and shapes which have potential for drug delivery. The transition temperatures of the proteins were measured using spectrophotometry for various protein concentrations, salt concentrations, and pH values. The samples were also investigated using light scattering. In particular, dynamic light scattering was used to probe the size of the aggregates above and below the transition temperature.

Physics major Chandler Bernard spent his summer at a Research Experience for Undergraduates (REU) program in the microelectronics-photonics department at the University of Arkansas. His research involved colloidal CdSe quantum dot nanocrystals, which are nanoparticles with their electrons confined quantum mechanically. These quantum dots also exhibit photoluminescence, which is the emission of light through absorption of photons. Due to their tightly controlled emission spectrum, quantum dot devices are in demand for industry for applications in photovoltaics and solar cells, as well as in medicine for imaging. Chandler's research aimed to use photoluminescence spectroscopy to characterize the dependence of photobleaching (the drop in intensity of emitted light due to exposure to laser radiation) as it depends on time and incident laser power density.

As a participant in UAB’s Research Experience for Undergraduates (REU) program, Troy University physics major Chandler Bernard spent the summer characterizing the spectroscopic properties of Transition Metal and Rare-Earth Metal doped ZnSe crystals for use in middle-infrared lasers. Mid-IR lasers are in high demand for medical diagnostics, industry process monitoring, and defense countermeasures. His most notable contribution was his characterization of absorption and transmission of Cr:ZnSe and Fe:ZnSe crystals with respect to increasing temperatures, with applications in tunable mid-IR lasers and the minimization of thermal losses in mid-IR laser cavities.