Events at Physics |
Events During the Week of October 22nd through October 29th, 2023
Sunday, October 22nd, 2023
- Outreach
- Saving Coral Reefs from Climate Change Through Science and Art
- Time: 2:00 pm - 3:00 pm
- Place: Madison Museum of Contemporary Art, 227 State Street Madison, WI, 53703
- Speaker: Pupa Gilbert, UW–Madison physics
- Abstract: At first look, Federico’s Uribe’s Plastic Reef (2018-2023) appears to be an underwater world filled with corals, mussels, and schools of fish. However, everything has been created and replicated using thousands of pieces of upcycled plastic carefully cut, dyed, and arranged. Discarded plastic bottles, cutlery, flip flops, and other plastic detritus that finds its way to the oceans, where it collects into “garbage islands” highlights the damage done to the oceans by pollution.
Pupa Gilbert will use the coral reef on display in Federico Uribe: Metamorphosis | Metamorfosis as a jumping off point to discuss how to save coral reefs and counter the damage of humans through from climate change. Gilbert is a Professor of Physics at the University of Wisconsin-Madison and a visiting faculty scientist at the Lawrence Berkeley National Laboratory.
This talk is presented in conjunction with the Wisconsin Science Festival. For more info: - Host: MMoCA, Wisconsin Science Festival
Monday, October 23rd, 2023
- Semiconductor Engineering Seminar Series: Rob Aitken
- The Most Important Thing is Everything – Building Chips in an Interconnected World.
- Time: 10:00 am - 11:00 am
- Place: TITU, Union South
- Speaker: Rob Aitken, Synopsys EDA Group
- Abstract: The CHIPS act and other announced government spending are designed to rebuild advanced semiconductor manufacturing capability in the US for national security and other purposes. This is an ambitious and laudable goal, with a huge number of interacting and interconnected technologies needed to bring it to fruition. This talk focuses on three of those: 3D integration of heterogeneous multi-die systems, advanced design technology, and novel computing system architectures. Each of these enables advances in performance and energy efficiency but even higher gains are attainable by co-developing all three together. These examples are not unique – the chips of the future will need a workforce with a broad range of skills and expertise to extract benefits from silicon that is increasingly challenged to provide them.
- Plasma Physics (Physics/ECE/NE 922) Seminar
- Non-disruptive tokamak operation far beyond traditional safety factor and density limits
- Time: 12:00 pm - 1:15 pm
- Place: 1610 Engineering Hall
- Speaker: Noah Hurst, UW-Madison
- Abstract:
See abstract and biography on attached file - Host: Prof. Steffi Diem
Tuesday, October 24th, 2023
- No events scheduled
Wednesday, October 25th, 2023
- Theory Seminar (High Energy/Cosmology)
- Resuscitating Yukawa's Bilocal Field Theory for Composite Scalar Bosons
- Time: 12:00 pm - 1:00 pm
- Place: Chamberlin 5280
- Speaker: Christopher T. Hill, Fermilab
- Host: Yang Bai
Thursday, October 26th, 2023
- R. G. Herb Condensed Matter Seminar
- First-Principles Many-Body Theory and Quantum Dynamics for Solid-State Materials
- Time: 10:00 am
- Place: 5310 Chamberlin
- Speaker: Yuan Ping, UW-Madison
- Abstract: Stable, scalable, and reliable quantum information science (QIS) is poised to revolutionize human well-being through quantum computation, communication and sensing. In this talk, I will show our recent development on first-principles computational platforms to study quantum coherence and optical readout as critical processes in QIS and spintronics in solid-state materials, by combining first-principles many-body theory and open quantum dynamics.
First, we will show how we reliably predict energetics, electronic and optical properties of spin defects and their host two-dimensional materials from first-principles many-body theory, which accurately describes highly anisotropic dielectric screening and strong many-body interactions. In particular, we will show how we predict spin-dependent optical contrast for information readout of spin qubits by computing exciton radiative and phonon-assisted nonradiative as well as spin-orbit induced intersystem crossing rates from first-principles.
Next, we will introduce our recently developed real-time density-matrix dynamics approach with first-principles electron-electron, electron-phonon, electron-impurity scatterings and self-consistent spin-orbit coupling, which can accurately predict spin and carrier lifetime and pump-probe Kerr-rotation signatures for general solids. As an example, we will show our theoretical prediction on Dirac materials under electric field to realize spin-valley locking with extremely long spin lifetime and spin diffusion length, and distinct dependence on electron-phonon couplings in spin and carrier relaxation in halide perovskites. This theoretical and computational development is critical for designing new materials promising in quantum-information science and spintronics applications. - Host: Alex Levchenko
- Astronomy Colloquium
- Cosmic ray electron re-acceleration in the intracluster medium via magnetic pumping
- Time: 3:30 pm - 4:30 pm
- Place: 4421 Sterling Hall
- Speaker: Aaron Tran, UW-Madison
- Abstract: Clusters of galaxies are embedded in a hot (T~10^7 K), low-density halo of gas called the intracluster medium (ICM). In some clusters, the ICM hosts low-frequency (MHz–GHz) radio synchrotron emission associated with radio galaxies, jets, and cluster merger-induced shocks and turbulence. The radio emission comes from GeV cosmic ray electrons (CRe). Some CRe may be "fossils", i.e., previously-accelerated CRe that then radiated and cooled to long-lived MeV energies. Fossil CRe are invisible until some perturbation, like adiabatic compression or turbulence, re-accelerates the CRe back to GeV energies. I will present a recent study of CRe re-acceleration via magnetic pumping, a mechanism in which small-scale (nanoparsec) plasma waves coupled to large-scale (kiloparsec to Megaparsec) motions can efficiently energize CRe. In 1D kinetic plasma simulations, we show that ion cyclotron wave scattering with background compression leads to resonant CRe gaining ~10-30% of their initial energy in one compress/expand cycle, assuming adiabatic expansion without further scattering. I will comment briefly on the applicability and limitations of this re-acceleration mechanism, and on prospects for future work.
- Host: Ke Zhang
Friday, October 27th, 2023
- Physics Department Colloquium
- Knowing So Little about So Much
- Time: 3:30 pm - 5:00 pm
- Place: Chamberlin 2241
- Speaker: Hooman Davoudiasl , Brookhaven National Laboratory
- Abstract: The dominant forms of matter and energy in the Universe are of unknown origin. In particular, the presence of dark matter (DM) - constituting roughly a quarter of the cosmic energy budget - has been established only through its gravitational effects and its nature remains largely a mystery. In this talk, we will briefly discuss some general aspects of DM theory and observation. It is possible that DM belongs to a separate sector, including various states and new forces. We will discuss some of the ways that such a sector may communicate with our visible world and reveal itself in current and future experiments.
- Host: Lisa Everett and Aki Hashimoto