Events at Physics |
Events on Thursday, September 26th, 2019
- R. G. Herb Condensed Matter Seminar
- Spin transport in ferromagnet-InSb nanowire quantum devices
- Time: 11:00 am
- Place: 5310 Chamberlin Hall
- Speaker: Vlad Pribiag, University of Minnesota
- Abstract: Topological excitations such as Majorana fermions provide unique pathways to fault-tolerant quantum computing. Recent progress in this direction has been enabled by proximity effects between non-superconducting materials and superconductors; however, further breakthroughs leading to topological quantum computation require developing new material systems that integrate semiconductors not only with superconductors, but also with epitaxial ferromagnets or antiferromagnets. Currently, Majorana devices based on semiconductors require application of an external magnetic field to induce spin splitting and open a helical gap – necessary to realize an odd-parity topological superconductor. However, the presence of this magnetic field limits the robustness of topological properties (by weakening the induced superconductivity). Moreover, the stringent requirements on its orientation with respect to the device greatly restrict the scalability of Majorana-based quantum information systems. A promising path forward is to realize Majorana modes without an applied magnetic field by closely integrating ferromagnets or antiferromagnets with semiconductors and superconductors. With this motivation, we have been studying ballistic InSb nanowire devices with ferromagnetic contacts [1]. I will discuss the results of magneto-transport measurements on these devices spanning from the many-modes regime to few modes, and will show that the magnetoresistance displays hysteretic features across this entire range of conductance regimes. I will discuss possible physical mechanisms underlying these observations, as well as implications for the development of Majorana devices that could operate without the need for external magnetic fields.
- Host: Alex Levchenko
- Cosmology Journal Club
- Time: 12:00 pm - 1:00 pm
- Place: 5242 Chamberlin Hall
- Abstract: Please visit the following link for more details:
http://cmb.physics.wisc.edu/journal/index.html
Feel free to bring your lunch!
If you have questions or comments about this journal club, would like to propose a topic or volunteer to introduce a paper, please email Ross Cawthon (cawthon@wisc.edu) and Santanu Das (sdas33@wisc.edu). - WISELI Seminar
- Physics In Concert With The Arts
- Time: 4:00 pm - 5:00 pm
- Place: 4274 Chamberlin Hall
- Speaker: Agnes Mocsy, Pratt Institute
- Abstract: This talk's journey will depart from the often present science-art dichotomy, exploring the complicated, often unexpected relationship that physics and the arts share. This complex relationship provides opportunities for fresh storytelling, in particular physics narratives embedded in a wider culture and interdisciplinary explorations in classrooms and beyond. I argue that science and the arts acting in concert may deliver benefits beyond science communication, addressing questions of social justice, and become an influencer of a more equitable world.
- Host: Women and Gender Minorities in Physics (GMaWiP)