Events on Tuesday, March 8th, 2022
- R. G. Herb Condensed Matter Seminar
- Simulating quantum many-body phenomena with superconducting qubits
- Time: 10:00 am - 11:00 am
- Place: 5310 Chamberlin Hall
- Speaker: Roman Kuzmin, University of Maryland
- Abstract: Superconducting circuits are ubiquitous in quantum simulations, computing, and metrology. In this talk, I will show a superconducting circuit platform extended to the extreme, in which the circuits actually become insulating. Remarkably, such nominally insulating circuits are a valuable resource. They create a tunable high-impedance environment and facilitate exceptionally strong interactions between photons and superconducting qubits. This opens up new directions for analog quantum simulations of interacting many-body problems, with examples ranging from quantum phase transitions to many-body localization. In particular, I will start with the demonstration of a dissipative quantum phase transition in a Josephson junction facing an Ohmic environment. Despite many experimental attempts, the existence of such a transition remains controversial. Using the high-impedance circuit environment, I will present evidence of the transition with a conceptually new approach, which relies on monitoring environmental degrees of freedom. A similar approach applies to analog quantum simulations of other strongly interacting models, which I will illustrate on two quantum impurity models relevant to the physics of Luttinger liquids and the Kondo effect. In the latter case, interactions induced by a quantum impurity in a finite size system allow us to observe the phenomenon of many-body localization. Finally, I will argue that the high-impedance circuit platform can contribute to the development of various areas of quantum science and technology.
- Host: Mark Saffman
- Outreach
- A Brief History of Time(keeping): Optical atomic clocks and their applications
- Time: 7:00 pm - 8:00 pm
- Place: UW Space Place, 2300 S. Park St or live on their YouTube Channel. See for details.
- Speaker: Shimon Kolkowitz, UW–Madison Physics
- Abstract: What would you do with a clock so accurate that it won’t gain or lose one second over the entire age of the universe? You could use it to test the theory of relativity and search for dark matter, among other things. Our speaker will help us understand how physicists use such amazing timekeepers for fundamental research.
- Host: UW Space Place