Light-Matter Interaction in 2D Flatland
| Date/Time: | Monday, 16 Sep 2019 from 4:10 pm to 5:00 pm |
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| Location: | Phys 0005 |
| Phone: | 515-294-5441 |
| Channel: | College of Liberal Arts and Sciences |
| Actions: | Download iCal/vCal | Email Reminder |
Abstract: Since the mechanical isolation of graphene - a single atomic layer of carbon atoms arranged in a chicken-wire pattern - in 2004, studies of atomically-thin two-dimensional (2D) crystals have evolved into a vibrant and exciting field expanding rapidly. Graphene keeps surprising us with its fascinating electronic properties. Other 2D materials, such as black phosphorus and transition metal dichalcogenides (TMDCs), open up new dimensions of fundamental research and device application. In this talk, I will introduce several fascinating developments in the field, and discuss our studies of these 2D materials harnessing light-matter interactions. These include development of graphene photosensors and investigation of manybody states in TMDC semiconductors. Our graphene photosensors are highly sensitive and extremely fast with bandwidth over 50GHz. The 2D TMDC semiconductor monolayers harbor robust valley and spin degrees of freedom. Strong Coulomb interaction in these isolated semiconductors produces versatile bound states consisting of two-, three-, four- and five-particles. Using a variety of optical techniques, we unambiguously determine their spin and valley compositions.
Bio: Prof. Jun Yan completed his PhD in 2009 from Columbia University in the City of New York. He worked as a postdoc at the University of Maryland College Park from 2009-2012. He is currently an associate professor of physics at the University of Massachusetts-Amherst. Dr. Yan's main research interest is in the studies of two-dimensional crystals, with an emphasis on their optoelectronic properties and fundamental excitations.