Events at Physics |
Events on Tuesday, April 23rd, 2024
- Preliminary Exam
- Nonlocal transport effects in electron bilayers
- Time: 12:00 pm - 2:00 pm
- Place: 5280 Chamberlin
- Speaker: Dmitry Zverevich, Physics Graduate Student
- Abstract: With the discoveries of novel materials, efforts are underway to create hybrid multilayers by stacking them together to form complex heterostructures and to explore new emergent fundamental physics governed by electron correlations. Experimental results on drag resistivity between quantum wires and double-layer graphene heterostructures triggered theoretical works, including new proposals for the mechanisms of this phenomenon. I am going to talk about the predictive theory of Coulomb drag and its relative phenomenon of near-field heat transfer in the context of correlated electron phases and investigate unexplored regimes of quantum transport in various mesoscale systems.
- Host: Alex Levchenko
- Council Meeting
- Physics Council Meeting
- Time: 3:00 pm - 4:00 pm
- Place: 2314 Chamberlin
- Speaker: Mark Eriksson, UW - Madison
- Host: Mark Eriksson
- Network in Neutrinos, Nuclear Astrophysics, and Symmetries (N3AS) Seminar
- Microscopic calculations of neutrino scattering and absorption in warm dense nuclear matter
- Time: 6:00 pm - 6:00 pm
- Place: Join Zoom Meeting Meeting ID: 912 3071 4547
- Speaker: Prof. Jeremy Holt , Texas A&M University
- Abstract: Numerical simulations of core-collapse supernovae, proto-neutron star cooling, and neutron star mergers require modeling of neutrino scattering and reaction rates that are sensitive to medium effects, including nuclear mean fields and correlations. In the past, it has been found that nuclear mean fields play an especially important role for enhancing electron-neutrino absorption and suppressing antineutrino absorption in warm and neutron-rich nuclear matter. In the present study, we investigate nuclear correlations on equal footing to mean fields through the random phase approximation (RPA) computed from microscopic models of the nucleon-nucleon interaction derived from chiral effective field theory. We find that RPA calculations generically indicate the presence of nuclear collective modes, which at low neutrino energies tend to suppress neutrino absorption and enhance antineutrino absorption, opposite to the effect of mean fields. We conclude that nuclear correlations should be treated on a consistent footing with mean fields in deriving neutrino charged-current reaction cross sections for astrophysical simulations.
Topic: N3AS online seminar series - Spring 2024 #7
NOTE: All participants and hosts are now required to sign into a Zoom account prior to joining meetings hosted by UC Berkeley.
PLEASE NOTE THE UNUSUAL TIME. - Host: Baha Balantekin