Events at Physics
Events on Thursday, April 25th, 2019
- R. G. Herb Condensed Matter Seminar
- Realistic numerical modeling of Majorana nanowires
- Time: 10:00 am
- Place: 5310 Chamberlin Hall
- Speaker: John Gamble, Microsoft
- Abstract: Using the Majorana zero modes of one-dimensional systems as topological qubits has recently generated considerable interest, with experimental efforts progressing rapidly, necessitating increasingly intricate qubit encoding schemes and layouts. Moving from a sketch of a complex design to a physical layout is a daunting engineering challenge, as small details of the design can have large impacts on device operation. Here, we present a computational tool chain that simulates the physics of these devices from the CAD schematics used for fabrication. By systematically varying the designs, we perform high-throughput computations to probe vast swaths of design space. Our simulations take into account the physical effects of self-consistent screening and superconductivity, while also including the detailed geometric configurations and fringing fields that are critical to device performance. Finally, we show validation comparisons with recent experiments in nanowire systems.
- Host: Friesen
- Cosmology Journal Club
- Low-Redshift Hydrogen Intensity Mapping
- Time: 12:30 pm - 1:30 pm
- Place: 4274 Chamberlin Hall
- Speaker: Trevor Oxholm
- Abstract: Special Session! Note change in time and location! Trevor Oxholm will be presenting his Prelim: "Low-Redshift Hydrogen Intensity Mapping"
- Astronomy Colloquium
- The Central Engine and Outflows in the Nuclear Starburst of NGC 253 as Revealed by ALMA
- Time: 3:30 pm - 5:00 pm
- Place: 4421 Sterling Hall, Coffee and cookies 3:30 PM, Talk begins 3:45 PM
- Speaker: Albert Bollato, University of Maryland
- Abstract: Starbursts are a rare phenomenon in the present day universe, but they represent perhaps the most common mode under which stars form and galaxies grow during the z~1-2 peak of cosmic star formation activity. Feedback, in the form of galaxy-scale outflows, is thought to be one of the main forms of regulation of galaxy growth. NGC 253 is the premier local example for a nuclear starburst, and has been targeted with several ALMA observations in order to study how these processes work. I will discuss the properties of the molecular outflow, including our best constraints on the mass and outflow rate, and the properties of the outflowing molecular gas. I will also present the results of our recent 1.7-pc resolution observations, including the detection and properties of 14 compact structures with properties corresponding to massive young star clusters and super star clusters, 13 of which are so embedded that are invisible in optical and NIR observations (the 14th is a known SSC). I will also discuss the evidence for feedback and disruption on the scales of these clusters. Finally, I will present a preliminary analysis of the 0.5-pc resolution observations recently obtained.