Events at Physics |
Events on Friday, October 18th, 2024
- Preliminary Exam
- Gate tunable spin splitting of germanium quantum well Josephson junctions
- Time: 1:00 pm - 3:00 pm
- Place: 5310 Chamberlin Hall or
- Speaker: Avani Vivrekar, Physics PhD Graduate Student
- Abstract: In my prelim exam, I will discuss Andreev spin qubits, a novel super-semi hybrid platform for quantum computation. Proximitized germanium (Ge) heterostructures are a promising host platform for Andreev qubits due to their strong spin-orbit coupling, high mobility, and naturally low nuclear spin abundance. A key distinction between Ge and traditional materials used for Andreev qubits, such as indium arsenide (InAs), is the form of their Rashba spin-orbit coupling, which is linear in momentum for InAs but cubic for Ge. In this talk, I will compare the effects of linear versus cubic spin-orbit coupling on the physics of Andreev qubits. I will also discuss the impact of charge defects on Andreev spin qubits in both InAs and Ge and explore the implications of these analyses for implementing Andreev spin qubits using Ge.
- Host: Mark Friesen
- Physics Department Colloquium
- Backlighting the large-scale structure with the cosmic microwave background
- Time: 3:30 pm - 4:30 pm
- Place: 2241 Chamberlin
- Speaker: Emmanuel Schaan, Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), Stanford
- Abstract: Upcoming large-scale structure (LSS) and cosmic microwave background (CMB) experiments offer a unique opportunity to turn the Universe into a particle physics laboratory and determine the nature of dark matter, dark energy, and the masses of the neutrinos. I will present innovative methods to jointly analyze these datasets and unleash their full constraining power. My group's research explores two powerful ways of using the CMB as a backlight for the LSS: revealing the invisible dark matter (gravitational lensing) and baryons (Sunyaev-Zel'dovich and patchy screening effects) via their shadows on the CMB. These methods will yield percent-precision maps of the dark and baryonic matter on cosmic scales, from combinations of CMB experiments like the Atacama Cosmology Telescope, Simons Observatory and CMB-S4 with LSS experiments like the Dark Energy Spectroscopic Instrument and the Rubin Observatory. These will not only shed light on dark matter, dark energy and the neutrinos, but they will also constrain models of inflation and transform our understanding or galaxy formation.
- Host: Moritz Muenchmeyer