Events at Physics
Events on Tuesday, January 17th, 2017
- Atomic Physics Seminar
- Quantum Control of Ultracold Dipolar Molecules
- Time: 12:00 pm
- Place: 5280 Chamberlin Hall
- Speaker: Huanqian Loh, MIT
- Abstract: Polar molecules offer long-range anisotropic interactions, which are fundamental to a wide variety of phenomena, from ferrofluid behavior to the folding of proteins. Recent demonstrations of cooling and trapping polar molecules have made it possible to study these particles in the quantum regime, making them highly attractive for applications such as quantum information storage and exploring novel condensed matter phases. In this talk, I will report on the quantum control of dipolar fermionic NaK molecules, which we have synthesized in the ground state at ultracold temperatures as low as 300 nK. Using microwaves, we have coherently manipulated not only the rotational states of the molecules, but also the nuclear spin degree of freedom. I will present our observation of nuclear spin coherence times on the scale of 1 second, and discuss its implications for quantum memory and probing new physics via Hertz-level precision spectroscopy.
- Host: Thad Walker
- Chaos & Complex Systems Seminar
- How worried should we be about congenital Zika virus?
- Time: 12:05 pm - 1:00 pm
- Place: 4274 Chamberlin
- Speaker: Dave O'Connor, UW Department of Pathology and Laboratory Medicine
- Abstract: I will talk about Zika as an example of what happens when a new virus that we know little about emerges, discuss what we've learned about Zika, and then talk about what factors might govern the emergence of such viruses that could threaten human health in the future.
- Host: Clint Sprott
- Theory Seminar (High Energy/Cosmology)
- The Fate of Axion Stars
- Time: 3:30 pm
- Place: 5280 Chamberlin
- Speaker: Hong Zhang, Ohio State
- Abstract: If the dark matter consists of axions, some of it will condense into axion stars, which are gravitationally bound Bose-Einstein condensates of axions. If an axion star accretes enough axions to exceed a critical mass, it will collapse. The fate of a collapsing axion star has not been established. One possibility for the remnant is a much denser axion star in which the attractive forces of gravity and axion pair interactions are balanced by the mean-field pressure of the axion Bose-Einstein condensate. A nonrelativistic effective field theory for axions can provide insights into the fate of axion stars. The collapsing process of axion stars and the possible denser remnant produce unique monochromatic radio-frequency signals at odd-integer harmonics of the fundamental frequency set by the axion mass.
- Host: Josh Berger