Bulletin of the American Physical Society
2021 Virtual Conference for Undergraduate Women in Physics
Friday–Sunday, January 22–24, 2021; Virtual
Session U23: High Energy and Condensed MatterInteractive Live
|
Hide Abstracts |
Chair: Elizabeth Zhou |
Sunday, January 24, 2021 12:00PM - 12:10PM |
U23.00001: Multi-orbital Flat Band Ferromagnetism with a Provable Percolation Representation Junjia Zhang, Eric Bobrow, Yi Li We consider a two-layer multi-orbital system consisting of a $p_x$, $p_y$-orbital honeycomb lattice layer and an $f$-orbital triangular lattice layer whose sites aligned with the centers of the honeycomb plaquettes. With an appropriately tuned chemical potential difference between these two layers, the system exhibits a flat band with provably ferromagnetic ground states at half filling of the band in the presence of intra-orbital Hubbard interactions and Hund's coupling. Away from half filling, the interacting system admits a percolation representation, where the ground state space is spanned by maximum-spin clusters of localized single-particle states. A paramagnetic-ferromagnetic transition occurs as the band approaches half filling and the can be analyzed numerically as a weighted percolation problem via monte carlo simulation. [Preview Abstract] |
Sunday, January 24, 2021 12:10PM - 12:20PM |
U23.00002: Characterization of the Cross Resonance Effect for Superconducting Transmon Qutrits Merrell Brzeczek, Alexis Morvan, Ravi Naik, Bradley Mitchell, David Santiago, Irfan Siddiqi A qutrit architecture proposes several resource-efficiency related advantages over qubit processors, but still lacks reliable high-fidelity entanglement gates. Currently, one of the foremost mechanisms for qubit entangling gates is the cross resonance effect, which has enabled high-fidelity quantum computation. The cross resonance interaction can be described by an effective Hamiltonian, which has been thoroughly studied for qubit systems. However, such characterization is still missing for qutrit systems. In this work, we experimentally characterize the cross resonance effect between two fixed frequency transmons from a qutrit perspective.This work is a step towards engineering high-fidelity two-qutrit entangling gates. [Preview Abstract] |
Sunday, January 24, 2021 12:20PM - 12:30PM |
U23.00003: Electrons for Neutrinos: Lepton Energy reconstruction in the Resonance Excitation Region Alicia Mand, Mariana Khachatryan, Afroditi Papadopoulou, Adi Ashkenazi, Florian Hauenstein, Anjali Nambrath, Lawrence B. Weinstein, Or Hen, Lucas Tracy, Stuart Fegan An area of particular interest in particle physics is neutrino oscillation. The nature of these oscillations remains unexplained by the standard model of particle physics. Neutrino oscillations are defined as the oscillating probability of a neutrino to be in a particular state as it travels through space. This is represented as a function of their propagation distance over their energy ($L/E$). However, the energy ($E$) is not directly measurable. Because of this, experiments rely on phenomenological models such as GENIE to reconstruct E. Through the use of electron data with known beam energies from the CLAS detector at the Thomas Jefferson National Accelerator Facility, the similarities between electron-nucleus and neutrino-nucleus interactions can be exploited. Using data from a variety of targets and known beam energies, we are able to test the GENIE interaction model. We found that the discrepancy between the data and the GENIE model were significant enough to show that GENIE can bias the energy reconstruction of neutrino-nucleus interactions. This presentation will be taking a look at the results generated from the analysis of the 1p1pi channel using the aforementioned data and the GENIE model. [Preview Abstract] |
Sunday, January 24, 2021 12:30PM - 12:40PM |
U23.00004: Comparing the Effects of Annealing and on the Magnetic Properties of High Entropy Alloys Lizabeth Quigley, Dustin Gilbert, Nan Tang, Walker Boldman, Cameron Jorgensen, Rémi Koch, Daniel O'Leary, Hugh Medal, Philip Rack High entropy alloys often have unique magnetic properties but are challenging to predict or design. In this work, we prepared two wafers made of Cr, Mn, Fe, and Ni using room temperature combinatorial sputtering. This technique results in a compositional gradient across the wafer, allowing a range of samples to be prepared at once. The as-grown wafer showed a single BCC structural phase and no chemical ordering. The second wafer was annealed at 600\textdegree C and showed large single-phase regions with BCC and FCC ordering. The difference between the two wafers allows for the effects of structural ordering and composition to be separated. The as-grown wafer showed superparamagnetic tendencies at higher temperatures, which resolved to both ferromagnetic and antiferromagnetic phases at low temperatures; exchange bias including loop shift and enhanced coercivity was observed. The as-grown wafer also showed a divergent coercivity at temperatures below 50K. The annealed wafer showed a larger Curie and saturation magnetization. However, the temperature dependence of the coercivity observed in the as-grown wafer was all but suppressed. This work shows the important role of ordering in high entropy alloys and explores a new parameter space which is inaccessible by traditional bulk synthesis techniques. Understanding the roles of composition and processing, and how they affect their properties, is critical for improving this field and eventually designing these materials. [Preview Abstract] |
Sunday, January 24, 2021 12:40PM - 12:50PM |
U23.00005: Development of control in brain networks over temporal and spatial scales using graph models Lindsay Smith, Harang Ju, Danielle Bassett Regions of the human brain vary in their capacity to control whole brain activity, in large part due to their location in the underlying structural network of interconnections crisscrossing the cortex. Recent work suggests that this capacity for control differs across spatial and temporal scales of the brain’s dynamics and can be formally probed using the Laplacian eigenspectrum of the brain’s structural network. Yet how such spatiotemporal control might differ from one human to another, potentially supporting and explaining differences in cognitive function, remains unclear. Here, we address this question by measuring several summary statistics of spatiotemporal control from human brain network architecture, as reflected in diffusion tensor imaging data acquired from 882 youth between the ages of 8 years and 22 years. We found that distinct features of network topology are correlated with a region’s capacity to enact distinct control strategies, and we investigate these relationships as a function of discrete timescales, from markedly slow modes of dynamics to relatively swift modes of dynamics. Our results provide insight into how local variation in connectivity gives rise to distinct processes of global control as a function of timescales over modes of activity. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700