Semimetals Unlimited: How New Materials are Redefining What is Possible in Solid State Electronics
| Date/Time: | Wednesday, 20 Feb 2019 from 4:10 pm to 5:00 pm |
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| Location: | TBA |
| Phone: | 515-294-5441 |
| Channel: | College of Liberal Arts and Sciences |
| Actions: | Download iCal/vCal | Email Reminder |
Abstract
Modern electronics is built on semiconductors, whose usefulness comes from their ability to switch between acting like a metal and acting like an insulator. For practical applications, however, semiconductors face certain unavoidable limitations imposed by the physics of localization and by the disorder introduced any time additional electrons are injected. In this talk I discuss whether these same limitations apply to nodal semimetals, which are a new class of three-dimensional materials that can be thought of as intermediate between metals and semiconductors. I show that, surprisingly, in a certain class of nodal semimetals the electronic mobility can far exceed the fundamental bound that constrains semiconductors. I then discuss the thermoelectric effect in semimetals, and show how the thermopower can grow without bound under the influence of a strong magnetic field. This large thermopower apparently enables the development of thermoelectric generators and refrigerators with record-large efficiency.
Bio:
Brian Skinner spent his undergraduate years at Virginia Tech, where he majored in physics and mechanical engineering. He then went to the University of Minnesota, where he received a PhD in theoretical condensed matter physics under the supervision of Boris Shklovskii. He spent two years at Argonne National Laboratory as the Eugene Wigner Postdoctoral Fellow before moving to MIT, where he is currently a postdoctoral researcher. Brian writes a popular physics blog called Gravity and Levity, and these days he is probably best known for having pointed out a suspicious repeated noise pattern in a paper claiming room temperature superconductivity.