Edwin Thompson Jaynes Fellowship Symposium

Every Fall Semester, the Department of Physics hosts the Jaynes Fellowship Symposium. This engaging event highlights the incredible work being done by our Edwin Thompson Jaynes postdoctoral fellows.

This year, we're excited to hear from Christopher Cappiello and Dmitry Chichinadze, who will each deliver ~25 minute talks on their research. 

Dark Matter Scattering in the Earth: the Good, the Bad, and the Melting of the Core with Chris Cappiello

It is usually assumed that dark matter interacts very weakly with Standard Model particles, and that this is the reason it has not been detected. However, it is possible that dark matter does interact somewhat strongly, and has not been detected because it is too light to trigger detectors, or because its interactions have an energy threshold (i.e., inelastic dark matter). In such cases, dark matter could scatter with nuclei in the Earth before reaching a detector. As I will discuss in this talk, such scattering can prevent dark matter from reaching a detector, or, for some models, can actually make it easier to detect. I will conclude with a discussion of how dark matter annihilation inside the Earth could actually melt parts of the inner core, allowing the planet itself to act as an enormous dark matter detector.
 

Electrons Going Nonlinear: Second-order Corrections to Ohm’s Law in 2D Materials with Dmitry Chichinadze

The history of nonlinear responses in physics is long and rich. Although they were first considered as early as 1968, only recently quadratic-in-electric-field corrections to Ohm’s law begun to regain attention. In the age of topology in condensed matter physics, it has been recognized that nonlinear responses can be triggered by nontrivial Berry curvature or quantum geometry in a system. This realization has led to significant experimental efforts and the discovery of giant nonlinear responses of 2D materials using both Hall-bar and disk-geometry samples. Microscopic theoretical calculations have shown an apparent discrepancy between the measured and calculated magnitudes of the effect — a phenomenon that remains not fully understood. In this talk, I will discuss contributions to second-order nonlinear transport in 2D materials that have not received adequate theoretical treatment and outline my work on building a microscopic theoretical framework to describe these phenomena.