Whether they are collaborating with faculty at Rhodes or participating in one of the many NSF sponsored Research Experiences for Undergraduates programs, students are encouraged and supported in research activities. It is not unusual for a graduating senior physics major to have attended several national meetings and given formal presentations to both research audiences in their field of work as well as general audiences in a seminar presentation.
Students can work with Rhodes faculty in research or apply for external research opportunities. They are encouraged to do both, and experience different research areas and types of research institutions in order to help clarify their long-term career goals.
CubeSat Project
Rhodes has an exciting ongoing multi-disciplinary research project. Rhodes is going to space! Its satellite, that is. RHOK-SAT is a one unit CubeSat (a 4-inch cube) that will be launched in 2023 to investigate the degradation of novel photovoltaic materials in a space environment. Rhodes' application to the NASA CubeSat Launch Initiative was accepted in April 2021, giving RHOK-SAT a ride into orbit. A team of about a dozen students are currently engaged in payload design and testing, flight software development, and ground station communications in anticipation of our year-long mission. We welcome students interested in joining this research project. Read more about it here: Nasa to Launch Rhodes-Designed Satellite into Space.
All faculty members in the department of physics routinely work with students on research in their areas of expertise. Descriptions of ongoing research by Rhodes Physics faculty are as follows:
Electrostatics
The interaction of two charged conducting spheres is a problem in classical electrostatics that has relevance in many natural and industrial phenomena such as the interaction of rain droplets in clouds, dust adhesion to surfaces, electrospraying, electrostatic printing, etc. The goal of this research is to understand this interaction at a fundamental level and develop mathematical approximations that are easy to use for quick and accurate calculations. The results can be used to simulate the dynamics of charged particles and for testing electrostatic (Laplace’s equation) solving software against exact mathematical formulae.
Mathematical Physics
The two-sphere electrostatics problem discussed above uses the mathematics of Lambert series. This series appears in mathematics of many other areas of physics and mathematics such as super-symmetry, prime number theory, etc. The research in this topic involves applying Lambert series results to new areas of physics which involve similar mathematical structures.
Ultrasonic Backscatter for Clinical Bone Assessment
Our research involves the development of ultrasonic techniques that can be used to detect changes in bone caused by osteoporosis. Osteoporosis is a degenerative bone disease that decreases the structural integrity of bone and increases the risk of fracture. Approximately 150 million people worldwide are at risk of osteoporotic fracture including hip fractures which are especially debilitating. The one-year mortality associated with hip fractures caused by osteoporosis is approximately 30%. Most individuals who suffer hip fractures never regain pre-injury status.
The Physics Laboratory for Ultrasonic Studies (PLUS) at Rhodes is pioneering new ultrasonic techniques that can be used to detect changes in bone and screen patients for osteoporosis. Specifically, we are developing backscatter methods of ultrasonic bone assessment. Backscatter measurements are performed by propagating ultrasonic pulses into regions of porous bone tissue called cancellous bone and then receiving the returned (backscattered) signal. The backscatter signals are analyzed in novel ways to estimate the density and microstructural characteristics of bone. Backscatter techniques may make it easier to perform ultrasonic measurements at clinically important skeletal locations such as the hip and spine where approximately two-thirds of osteoporotic fractures occur. Also, it may be possible to adapt ultrasonic imaging systems already in clinical use for other purposes to perform backscatter measurements on bone.
Witnessing the circumgalactic medium in formation: Imaging highly-ionized oxygen in a record-breaking galactic wind using the Hubble Space Telescope.
The massive, compact galaxy Makani hosts perhaps the largest starburst-driven galactic wind yet detected. This wind (see video) extends well into the circumgalactic medium (CGM) of its host galaxy and is a snapshot of the CGM-in-formation. The enormous and luminous oxygen nebula in Makani is the ideal target to image the warm-hot CGM, which is difficult in most other sources. During 2021 and 2022, we are making the first "rebirth picture'' of the warm-hot CGM as it is being formed anew by the giant wind in Makani. We are imaging Makani with the ultraviolet camera on the Hubble Space Telescope (ACS/SBC). These observations are optimally-timed to meet simulated images of OVI that are emerging from the latest simulations. The morphology of the image and comparison with other data will constrain the physical state of the gas in the nebula through comparison with models and simulations of the wind-CGM interaction and shock+photoionization models.
Q-3D: Imaging Spectroscopy of Quasars with the James Webb Space Telescope
In the last few years, integral field spectroscopy has revolutionized extragalactic astronomy. The unprecedented infrared sensitivity, spatial resolution, and spectral coverage of the new James Webb Space Telescope IFUs will ensure high demand from the astronomical community. Our team, including Rhodes students, are providing the community with a new spectral analysis package for high dynamic range JWST IFU observations. Luminous quasars, with their bright central source (quasar) and extended emission (host galaxy), are excellent test cases for this software. Quasars are also of high scientific interest in their own right as they are widely considered to be the main driver in regulating massive galaxy growth. JWST will revolutionize our understanding of black hole-galaxy co-evolution by allowing us to probe the stellar, gas, and dust components of nearby and distant galaxies, spatially and spectrally. We will use the IFU capabilities of JWST to study the impact of three carefully selected luminous quasars on their hosts.
Biomaterials, both synthetic and naturally occurring, are an increasingly important part of our daily lives, and characterizing their physical properties is essential for understanding and improving their performance. Dr. Viano's research focuses on the investigation of these materials in various biological environments. She is a member of the Physics Laboratory for Ultrasonics where ultrasound is used to characterize different types of biological tissues or materials. Measurements of backscattered ultrasound allows for the study of mechanical properties of bone and other tissues, from both direct signal measurement and image analysis. Measurements of ultrasound propagated through a material allows for the characterization of time-varying properties such as the stiffness of curing bone cement.
Dr. Viano has also participated in biomedical imaging research using magnetic resonance imaging (MRI). With collaborators at St. Jude Children's Research Hospital, she has modeled brain activity using functional MRI and worked to improve MRI imaging for patients with metallic implants.
Dr. Viano has also investigated other implant materials such as ultra-high molecular weight polyethylene, the material used to simulate cartilage in large human joint prostheses such as hip and knee replacements. She investigated degradation of that material due to wear on the molecular and atomic levels using transmission electron microscopy. Further work on prostheses included studies of the corrosion of metallic implant components in wound healing environments using electrochemical methods.
Lab-on-Chip Methods for Trapping and Transporting Magnetic Particles in Fluids
Our modern world relies heavily on chip-based technologies for electronic items such as computers and cell phones. The preceding decades have led to many advances in the production of these chips, and in turn humans have been able to make large quantities of chip-based electronic devices at increasingly low prices; there are now more cell phones than people. In recent years, chip-based technologies have not only been used for electronics, but also in “lab-on-chip” microfluidic devices where miniature biology, chemistry, and medical experiments can be done on a chip the size of a coin. This has been used for, for example, detection of pathogens or nucleic acids from a very small amount of liquid input.
We are interested in one technique relevant to lab-on-chip devices, namely how surface-patterned magnets on the chips interact with magnetic particles in water, or “magnetic beads”. These patterned magnetic structures are smaller in width than a human blood cell and only a few hundred atoms thick, but have been shown to be able to trap beads on the surface. In addition, by using electromagnets to apply and vary magnetic fields, beads can be transported across surfaces in controlled ways, as seen below. We are interested in the underlying physics behind how these interactions work. Additionally, this trapping and transport mechanism has already been shown to have applications in, for example, magnetically-actuated microscopic fluid pumps and new ways of detecting rare molecules, and we are working on developing new applications of this powerful and versatile tool.
The physics department keeps a listing of great info about research programs across the country, and updates it as new opportunities are announced. Rhodes physics students have been accepted to summer research internships at institutions across the country and globe, and have worked on projects spanning all areas of physics.
