Student-Faculty Research 2017
Physics major Marissa Dierkes works on a research project aimed at optimizing electrical biosensors that use random carbon nanotube thin-film networks as the active sensing layer.
Student-faculty research is thriving in the Physics Department. Students discover how to approach new questions and build their confidence through designing and running experiments, co-authoring peer-reviewed papers and presenting at professional conferences. From nantobues to black holes, the universe is their laboratory. Learn more about their projects below.
Thermoelectric Clathrates and Thermoelectric Power Generation
Thomas Linker displays the research poster
that he presented at the International
Conference on Thermoelectrics in Pasadena.
Beekman, physics major Thomas Linker and materials engineering major Glenn Lee investigated different models to predict the efficiency of thermoelectric devices, which convert heat to electrical energy. Physics student Aaron Vandergraaf joined Beekman to explore high-temperature thermal conductivity of thermoelectric clathrates. Semiconducting clathrates also have possible applications in converting heat to electrical energy. Both Linker and Vandergraaf co-authored peer-reviewed papers as a result of their research.
Beekman also spent the summer as a visiting researcher at the Max Planck Institute for Chemical Physics of Solids in Dresden, Germany, as part of a collaboration on intermetallic clathrate materials.
Supermassive Black Holes
Students (left to right )Priscilla West, Chance Spencer
and Ellen Glad in front of the one-meter Nickel
telescope during their training at the Lick Observatory.
For a two-year period, Vardha Bennert and her team of international collaborators will have viewing time on the Hubble Space Telescope (HST), which will obtain high spatial resolution images of a sample of 84 nearby active galaxies. These images will be used for detailed morphological classification of the host galaxies using 2D decomposition techniques. The team is investigating the relationship between the properties of the galaxies and the masses of the supermassive black holes at their centers. The data from the Hubble observations will be studied alongside spectra taken by the 10-meter Keck telescope in Hawaii. The award of HST time comes with more than $110,000 funding from NASA for data reduction, analysis and publication.
A team of five physics majors has been conducting observations by controlling the Lick Observatory’s one-meter Nickel telescope remotely from Cal Poly. The students traveled to the Lick Observatory for training and then designed the remote observations themselves, including planning, coordinating, organizing, conducting and reporting. They are monitoring the variability of active galaxies with the goal of measuring their black hole masses. One of the students, Isak Stomberg (B.S., ’17), helped write the proposal to receive time on the HST. So far, the Cal Poly team has conducted 15 nights of observations with a total of 12 visitors, including local high school students, Cal Poly students taking astronomy as a general education class, and physics majors focusing on astronomy.
Brightest Cluster Galaxies
This image from NASA's Hubble Space Telescope shows
the elliptical brightest cluster galaxy ESO 325-G004
at the center of galaxy cluster Abell S0740.
Louise Edwards gave an invited talk at the Galaxy Clusters 2017 conference in Spain, showcasing work from physics majors Matthew Salinas, Steffanie Stanley and Priscilla West. Edwards and the student researchers are investigating brightest cluster galaxies.
The largest objects in the universe today are clustered groups of hundreds of galaxies that move around each other under the influence of gravity. Each galaxy is composed of billions of stars, but one, the brightest cluster galaxy, is often several times the mass and size of all the others and found exactly at the cluster's center. Scientists still don’t know how these massive galaxies grew to their present size and location, and the Cal Poly researchers look at evidence for and against various formation scenarios. The students worked directly with a dataset that suggests these galaxies build from the inside out.
Black Holes and Time Travel
Laura Fleischman took second place at the 2017 CSU Student Research Competition for her work on the unique necklace-like "beads-on-strings" structure formed by unstable black strings (cylindrical black holes). This work plumbs the depth of black holes' known fluid behavior and is currently in being prepared to submit for publication.
Last summer, Fleischman followed a spin-off project of refining an energy-conservation model to predict the black string's evolving beaded shape; the goal is an analytical understanding of the only known limited numerical data. She found that the simplest conservation model worked well in one direction (numerical values input into an analytical formula) while in the other direction, it was extremely sensitive to parameters. To address this, she and Fraser augmented the setup by calculating the gravitational interactions among the thin "string" segments and the black hole "beads."
Fleischman’s calculations potentially open up a new frontier in black hole physics because they describe how an extended "lumpy" black horizon physically interacts with itself, which has never explicitly been done before.
Sebastian Pardo used a mathematical "embedding" technique to match the known flattened shapes of black holes (attached to membranes) to the shapes of fluid droplets on membranes (like water droplets that bead up on a windshield). Pardo and Fraser refined the fitting of two shape parameters for the fluid droplet down to a one-parameter search technique. This extends the work of a previous student to be one step closer to a form suitable to submit for publication. Intriguing future applications are to physically interpret the fluid parameters in terms of the black hole's properties and/or the properties of the "dark energy" that surrounds this black hole (similar to the dark energy measured in our universe).
In summer 2017, Matthew Imbriani learned how to scientifically phrase his childhood dream of examining ways to "bend" time (the fourth dimension) in general relativity. Matthew found a high-impact journal publication with a proposed time travel mechanism, with spacetime features that match our known universe (unlike all other known similar mechanisms). Following Imbriani’s interest in this paper, he and Fraser found a way to extend the paper's unique-yet-simplified "circular" design by adding a gap that allows for the "jump in time" expected of a true time machine. They also examined the energy and pressure that would be required to build this time-travel device, which allowed them to identify a flaw in an analysis technique suggested in the paper.
Nathan Heston, Nik Glazar and Pete Schwartz
Direct DC Solar
The research team presents its insulated solar
electric cooker at the American Solar Energy
Society Conference in Denver.
During the past year, physics faculty members Nathan Heston, Nik Glazar and Pete Schwartz mentored an interdisciplinary team of 18 students in Direct DC Solar (DDS) and related technologies, collaborating with organizations and schools in the U.S. and Africa. DDS is inexpensive and could result in global energy transitions. In poor countries, DDS can provide communities with access to electricity for the first time. The research team is developing technologies for cooking and making ice while investigating insulation and thermal storage.
Eleven students were co-authors on a published paper that reviewed their development of Insulated Solar Electric Cooking and their implementation of the technology in Uganda in collaboration with the nonprofit Aid Africa. An accompanying video on Insulated Solar Electric Cooking is receiving attention, particularly in India.
In November, industrial technologies major Madison Fleming presented the solar cookers at MIT’s Women in Clean Energy Symposium, winning first place. In October, students Adeel Ali, Madeline Larkin, Nicholas Crawford and Joshua Dimaggio attended the American Solar Energy Society Conference in Denver with Heston and Schwartz and presented three talks and four posters.
The team also partners with PG&E-supported We Care Solar to bring electricity for lights and cell phones to the global poor. The program also entails developing a curriculum for Cal Poly students to teach local elementary and high school students about solar electric technologies and about the lives of those outside of the U.S.
As the team continues to develop the technologies and build a collaborative business model for dissemination, they are planning a summer 2018 trip to Africa to learn more about how people live there and collaboratively implement DDS technologies.
Memory Formation in Disordered Materials and the Properties of Active Fluids
Nathan Keim and his students are working on two National Science Foundation-funded projects. The first investigates memory formation in disordered materials. For example, when a piece of paper is crumpled or a bridge is driven over, the material “remembers” that action and its future behavior may be influenced. The second project deals with the properties of active fluids. The student-faculty research team will build a thin-film rheometer that will be used to measure bulk properties of active suspensions. Students Jacob Hass, Natasha Proctor and Jeanette Smit, who have been working with Keim, presented their work at the American Physical Society Far West Section meeting in Merced, Calif.
High Purity Single-Walled Carbon Nanotube Networks
Roger Martinez Reyes loads a carbon nanotube field
effect transistor device for electrical characterization.
As part of an international collaboration, Colleen Marlow was a co-recipient of the prestigious Marsden Award from the New Zealand Royal Society. The funding from the award will bring a doctoral student to Cal Poly to work with undergraduate students investigating the electrical sensitivity of randomly arranged, single-walled carbon nanotube networks using an AFM gating technique that Marlow and her group developed. The project aims to optimize electrical biosensors that use random carbon nanotube thin-film networks as the active sensing layer. These devices are used in point of care and remote biological detection.
Two students who have been working with Marlow on a related project, Marissa Dierkes and Roger Martinez Reyes, presented posters on their research at the American Physical Society Far West meeting at UC Merced in November.
Super-Proton Synchrotron (SPS) at CERN
Three students worked with Themis Mastoridis on a simulation of the accelerating system of the Super-Proton Synchrotron at the European Organization for Nuclear Research (CERN) in Geneva, Switzerland. They validated the simulation with measurements from CERN and then traveled to Geneva, where they presented their results and participated in discussions and experiments. The student researchers are now using the simulation to determine optimal operational parameters to maximize the number of accelerated protons.
Hydrodynamic Analogs of Optical Trapping
Nilgun Sungar gave a talk on hydrodynamic analogs of optical trapping at an international conference on quantum-hydrodynamic analogs in Belgium. During the summer, physics major Jessica Pilgram worked with Sungar’s collaborators at MIT on drop dynamics above the Faraday wave threshold.
Searching for Neutrinos in Antarctic Ice
Attendees at a four-day workshop on the ANITA
experiment hosted by Cal Poly.
Three students in the Wissel lab — Keith Lamy, Jenny Smit and Zoe Riesen — started the summer by attending an international collaboration meeting of physicists and ended the summer by conducting a large-scale experiment. Both the collaboration meeting and the experiment were held at Cal Poly.
Forty physicists from the U.K., Taiwan and the U.S. came to Cal Poly for a four-day workshop on the ANITA experiment, which searches for neutrinos in Antarctic ice. During the week, the students learned the details of the experiment, participated in a coding workshop, and met graduate students, postdocs and faculty from other institutions.
The meeting gave the three students a jumpstart on their individual research projects. Riesen performed a search for cosmic rays in ANITA data. Lamy worked toward remote control of the power systems on an experiment buried in the ice at the South Pole. Smit developed algorithms for using the sun as a calibration source on ANITA.
All three ended the summer by recreating an accelerator experiment originally performed at the SLAC National Accelerator Laboratory with a fast electron beam, a two-ton polyethylene target, and broadband antennas. This time they set up the target and receivers used in the original experiment here at Cal Poly in the Simpson Strong-Tie Building with the support of the Architectural Engineering department. However, rather than using an electron beam, they embedded a transmitter inside the target to better understand the systematics of the original accelerator experiment. This experiment was performed alongside researchers from UCLA, NASA’s Jet Propulsion Laboratory and Washington University in St. Louis.